Warned at Don Mueang Airport on my 4th entry- 2 SETV’s and second Visa exempt by air

Just wanted to let you guys know what happened earlier this week…I’ve seen similar posts but not one for only 4 entries. I have one SETV from Cambodia (extended), one SETV from Hong Kong (extended), one Visa Exempt Entry by air (arriving in Don Muang airport from Phnom Penh, extended), and had just arrived to get a second Visa Exempt (arriving at Don Muang from Hanoi).
I know that there is no limit on Visa Exempt entries by air, but also understand it is at the Immigration officer’s discretion. I just wanted to report back to you guys because I have seen an increasing number of these posts, especially from Don Muang. Sometimes followed by comments asking about nationality, tattoos, clothing, etc. I am early 40’s American (white), no visible tattoos, I was totally clean shaven, wearing a long sleeve button down collared designer shirt, long pants and closed shoes. Polite and friendly the entire time. So nothing I can imagine to cause any alarm. One small detail though- A female officer directed me to go to the Chinese Passport lane as there was only one person in queue, which I mentioned to the male officer behind the counter.
He looked at my Passport and said “This is very bad. You come here four times already.” I explained that I tried to get a tourist visa in Vietnam, but was unable to due to the TET festival (Vietnamese New Year- embassy closed all week). This was true and I had my bank statement showing just under 100k in a Thai bank, and Medical certificates for upcoming hospital appointments including a scheduled surgery in Thailand. I have some new inquiries on that now, but will stay on topic here. I was pulled aside to talk to a supervisor. He was smiling, friendly, and polite to me and my Thai gf who had been with me on the trip to Hanoi. But he warned me that I probably won’t get another tourist visa or be able to make another entry at all. When I pointed out I have this upcoming surgery, he advised I get the surgery first and then try to get another visa after the surgery (I won’t be able to walk for about 3 months…metal plate in my ankle is to be removed…initial surgery was also in Thailand).
I keep reading Thailand is promoting itself as a medical hub. And four entries is too many? Good guys in, bad guys out? How am I a bad guy? Could this just be a case of an immigration officer having a bad day? Should I be worried? I think I will avoid Don Mueang Airport even though I live 10 minutes away, about an hour or much more with trafficfrom Swampy. Just a head’s up and any thoughts or advice are welcome.
P.S. No check was done on any computer (I’ve seen inquiries and speculation on that) and nothing was written or stamped in my passport.