Does a non-used Schengen short-stay visa count to qualify for a one year visa?

Apparently, people can get a long stay (1-year) schengen visa if they are granted three short stay visas in a two-year period. If I am granted a short-stay visa, but am unable to travel (and therefore utilize the visa), does that count toward the three visas that make me eligible to apply for a 1-year visa? I have technically not violated the 90/180 rule in this case, but I'm wondering if I have to travel to EU for that visa to count toward the long-stay application.

There is some language along these lines in the Schengen Visa code and some other documents published by the European Commission but it's not that clear cut. I do think the unused visa should still count for something because it's not been used unlawfully but ultimately practice is very inconsistent and consulates do whatever they want. You cannot count on any number of visas leading to anything and you certainly cannot go to court to force the issue so at the end of the day, all you can do is apply and hope to be lucky.

Importantly, a one-year Schengen visa is not a long-stay visa under EU law. Schengen visas can be valid for up to five years but only ever allow the holder to stay for a maximum of 90 days at once in the Schengen area.

Long-stay visas are national visas allowing the holder to stay for more than 90 days in one of the Schengen area countries. The criteria are a matter for each country and depend on the specific category but earlier Schengen visas or short stays are essentially irrelevant to long-stay visa applications.

No.

The Schengen Visa Code tells us, in article 24:

2. Provided that the applicant fulfils the entry conditions set out in point (a) and points (c) to (e) of Article 6(1) of Regulation (EU) 2016/399, multiple-entry visas with a long validity shall be issued for the following validity periods, unless the validity of the visa would exceed that of the travel document:

(a) for a validity period of one year, provided that the applicant has obtained and lawfully used three visas within the previous two years;

(b) for a validity period of two years, provided that the applicant has obtained and lawfully used a previous multiple-entry visa valid for one year within the previous two years;

(c) for a validity period of five years, provided that the applicant has obtained and lawfully used a previous multiple-entry visa valid for two years within the previous three years.

Airport transit visas and visas with limited territorial validity issued in accordance with Article 25(1) shall not be taken into account for the issuing of multiple-entry visas.

(Emphasis mine)

So you need to have received and used the three visas.

However, note that it continues:

2a. By way of derogation from paragraph 2, the validity period of the visa issued may be shortened in individual cases where there is reasonable doubt that the entry conditions will be met for the entire period.

2b. By way of derogation from paragraph 2, consulates shall, within local Schengen cooperation, assess whether the rules on the issuing of the multiple-entry visas set out in paragraph 2 need to be adapted to take account of local circumstances, and of migratory and security risks, in view of the adoption of more favourable or more restrictive rules in accordance with paragraph 2d.

2c. Without prejudice to paragraph 2, a multiple-entry visa valid for up to five years may be issued to applicants who prove the need or justify their intention to travel frequently or regularly, provided that they prove their integrity and reliability, in particular the lawful use of previous visas, their economic situation in the country of origin and their genuine intention to leave the territory of the Member States before the expiry of the visa for which they have applied.

(emphasis mine)

So, really, they do whatever they want. They can grant you more, they can grant you less. Apparently some countries generally stick to the rule while others have a hard time giving longer-term visas. Or it may depend on the consulate or the citizenship or the applicants. Or a combination.

On the other hand, strong applications can get longer term visas pretty quickly, but if they haven’t done that for you already, it’s unlikely your application is strong enough for that (though it should become stronger with time).