I’m a Singapore resident and fly weekly between SG-TH, only been asked once, in many years, casually “wow why so many (entry) stamps”. I replied in Thai that I’m married to a Thai and didn’t require a marriage visa due to visa exempt.. and that was it, no other questions asked.
PS* I also always have my Thai marriage contract saved in photos just in case but never been asked for it.
Arrived BKK airport 11am, brought to car right away, went to drive-through swab then to hotel. Called reception at 7pm results were out. Left immediately!