it was that high in recent 2024....but all are now at US $16,000. BUT for applicants : it's Best to Read the Thai Embassy or Consulate website where you will be applying for their requirements.
Do yourself a BIG FAVOR...get the DTV visa in the USA before you travel to Thailand in September.
Otherwise, expect to be questioned by Thai Immigration Officers upon arrival into Thailand and possibly DENIED entry. Indeed you will be on their radar for trying to enter Thailand again as Visa Exempt Entry.
It's clear that Thai Immigration Officers are cracking down on those who like you, use Visa Exempt Entry into Thailand multiple times.