The visa exempt entry period has been 30 days for at least 25 years. It has not changed at all in at least that long except for fluctuations such as Covid limitations, temporarily granting 45 days during the post-Covid period, etc. If there was ever a 90 day exemption for US citizens, it would have been several decades ago.

LTR visa comes with some good perks for OP’s situation. Big ones could be exemption from the 4:1 Thai:foreigner ratio for employment, and tax exemption for overseas income. (The 17% rate only applies to highly skilled professional category, AFAIK.)

https://ltr.boi.go.th

Also when I arrive in Thailand I get stamped in until 2028. I never stay that long but if I did I would not have to do 90 day reporting either — only once per year reporting.