It is common not to use ESTA. In fact it is not mandatory to give travel dates or destination address.
Note: ESTA is not an authorization to entry in US, it is just a screening process: it simplify travel from countries which have few unauthorized immigrants, but also providing information to such citizens if they need to require a visa (so reducing problems/costs on entry). In addition, the data is used like an API (Advanced Passenger Information), so authorities can check on different databases if you are not welcome.
In any case, it is recommended not to book flights before getting ESTA or the visa, and in COVID times, I think it is normal to change plans. It was already so before COVID: business travel were often cancelled or moved, visits often changes, various sport or travel activities requires some conditions (weather, snow, etc. US is famous for its parks)., etc.
Credit:stackoverflow.com‘