So there are really two questions here:
To the first question, the answer is that the allowed activities on VWP are exactly the same as the allowed activities on a B-1/B-2 visa. However, one may not apply for an extension of stay, change of status, or adjustment of status while on VWP. (There are some exceptions to this rule.)
If you don’t believe me on this, here are the legal sources.
The Immigration and Nationality Act (INA) §217(a) lists the requirements that are imposed on the visitor themselves. There are various requirements that don’t apply to B-1/B-2 visitors (e.g. must be in possession of a round-trip ticket, must not have visited Iraq or Syria, and so on). However, the sole requirement on the allowed activities while in the US is:
(1) The alien is applying for admission during the program as a nonimmigrant visitor (described in section 1101(a)(15)(B) of this title) for a period not exceeding 90 days.
The Foreign Affairs Manual, while not binding, reflects the State Department’s official position regarding the appropriate uses of various visas. Regarding VWP, it mentions here:
An alien who is a national of a participating VWP country does not require a visa, provided the alien:
(1) Is applying for admission as a nonimmigrant visitor, as described in INA 101(a)(15)(B);
(2) Seeks to enter the United States for a period not to exceed 90 days;
…
and:
Nature of VWP Travel:
(1) Maintenance of Status: An alien admitted to the United States under the VWP:
(a) Is admitted as a visitor for business or pleasure for a period not to exceed 90 days;
(b) May not engage in activities inconsistent with status as a visitor;
(c) Is not eligible for an extension of stay in the United States;
(d) Is not eligible for adjustment of status to that of a lawful permanent resident alien (other than as an immediate relative as defined under INA 201(b) or under the provisions of INA 245(i); and
(e) Is not eligible for change of nonimmigrant status.
The CBP Inspector’s Field Manual may be more directly relevant to this situation since most ESTA applications are not manually reviewed by someone at the State Department but the determination of admissibility will be made at the port of entry. Regarding VWP, it says:
The Visa Waiver Program (VWP) permits nationals from designated countries (listed in 8 CFR 217.2(a)) to apply for admission to the United States for ninety (90) days or less as nonimmigrant visitors for business or pleasure without first obtaining a U.S. nonimmigrant visa (USNIV).
"Business or pleasure" is the same as a B-1/B-2 visa.
It also mentions:
An applicant for admission shall not be admitted under the VWP unless the alien convinces the examining immigration officer that he or she is clearly and beyond doubt entitled to be admitted and is not inadmissible under section 212 of the Act. The conditions for admission are specified in section 217 of the Act and 8 CFR 217. All VWP admissions are for 90 days unless the applicant’s passport is valid for a lesser period, in which case the period of admission would be until the expiration date of the passport for those countries on the 6-month list. In the cases of those countries not on the 6-month list, the applicants would not meet the documentary requirements in Chapter 15.7(b), Documentary Requirements, and would be inadmissible under the VWP.
This doesn’t add anything beyond the statute and regulations which already specify that VWP applicants may engage in the same activities as B-1/B-2 applicants. The "clearly and beyond doubt" standard applies to all nonimmigrant applicants for admission.
In short, if you believe that B-1/B-2 visa holders are allowed to enter the US to look for work, you should believe the same about ESTA holders.
And by the way, USCIS also recently weighed in on the question of whether B-1/B-2 nonimmigrants can look for a job. USCIS policy is technically not binding on State (which issues visas) and CBP (which processes travellers for admission), but whenever you apply for any immigration benefit from USCIS (such as a change of status to B-1/B-2, where you must establish that you seek to remain in the United States for activities that are permissible in B-1/B-2 status, or an adjustment of status, where USCIS will scrutinize whether you have ever violated US immigration law), their policies apply. And the USCIS policy states that "searching for work and interviewing for a position are permissible B-1 or B-2 activities". [Link]
Regarding the second question, my opinion is that you should just try to enter under VWP. It’s very unlikely that they will tell you "no, you have to apply for a B-1 visa for that" since they are supposed to know that the allowed activities are the same. If they do refuse you admission under the VWP, you are unlikely to be approved by ESTA in the future. However, that would also be the case if you were refused admission under a B-1 visa. So, to preemptively apply for a B-1/B-2 visa now would be pointless in my opinion. If you are reading this during the COVID-19 pandemic, trying to apply for a visa would needlessly inconvenience you because many consulates are not operating at full capacity anyway.
The answer is absolutely No as can be easily verified in zillions of sources.
(The unusually worded ambiguous information mentioned in the other answer, was once on a US embassy web site, but was removed as it was so confusing.)
It’s fairly annoying to have to explain this explicitly but:
The question was:
Can I travel to the United States on the Visa Waiver Program to find a job or attend interviews and then apply for the E-3 visa once I return to Australia?
could not be more different.
The question might as well ask,
"Can I travel to visit my grandmother or buy leopards"
"Can I travel to see the Grand Canyon or work for Microsoft".
and so on.
The question is meaningless.
The answer was:
Yes, you can travel on the Visa Waiver Program (VWP) if you meet the requirements (please see our page on the Visa Waiver Program)…
Note that the QA page was about the VWP specifically.
Since the question was meaningless – it asks two utterly different questions – the minimum-wage staffer from the embassy who wrote the answer just typed "you can use a VWP if you meet the requirements. See the actual facts on the VWP to see if you meet the requirements."
{And if you go there it, obviously, says "you cannot come to the US to look for a job". As on every other piece of information ever emitted by the US Government regarding visas!}
Equally obviously, this confusing answer was, of course, removed from the embassy web site.
As I say, it is fairly annoying to have to take time explain this explicitly because it is so glaringly obvious, and it is such an well-known fact that, of course, you cannot come to the US and look for a job.
Surely, surely, surely, surely folks as sophisticated internet users, as site visitors here, realize it’s a well known problem in the information age where you get one glaringly, obviously, wrong bit of text on the net (whether about programming, physics, or whatever) gets magnified by folks endlessly repeating it over years.
Yes.
From a visa website (since the original Embassy link is dead, but same content):
Question:
Can I travel to the United States on the Visa Waiver Program to find a
job or attend interviews and then apply for the E-3 visa once I return
to Australia?
Answer:
Yes, you can travel on the Visa Waiver Program (VWP) if you meet the
requirements (please see our page on the Visa Waiver Program). If you
do not meet the VWP requirements, you may be eligible to travel on the
B-1/B-2 Combined Visa for Business or Pleasure.You must leave the United States before applying for your E-3 visa.
Credit:stackoverflow.com‘