I'm really sorry to hear about the disruption to your plans.
I totally agree with gerefan2 and goji's read on this.
If the airlines see enough bookings coming through, they'll schedule their flights. If there aren't enough bookings for a particular destination, during a particular time period, they cancel the flights. It really is as simple as that.
There's no doubt that Thailand's primary objective is to be perceived as being one of the first SE Asian countries to reopen to tourism. I imagine they feel that creating this perception in the international tourist market gives them an edge. But on the other hand, they really don't want too many tourists actually coming here - at least at this juncture.
They control the flow by keeping the majority of bars and entertainment venues closed, alcohol bans, curfews, etc., and of course use the Delta Variant as an excuse for their decisions at every opportunity. Right now, I think it's fair to say that most tourists don't want to come to Thailand because of this. Results = THAILAND HAS REOPENED (perception created) = Mission accomplished.
All said, you, goji, gerefan2, and others, who have decided to brave the waters, know exactly what's going on here right now and should have a great time once you arrive. I don't imagine there're too many tourists out there who don't know what it's like in Thailand right now.
I would be doing exactly the same thing that you guys are doing if I was in your shoes. I said this a year ago, and I can say this again now washout hesitation. Having a place where the sun is shining...a beach for frolicking...and a boy to frolic with...is all that I would need. The alternative for me would be staring at the icicles hanging from the gutters of my apartment in Chicago playing with myself.
Good luck.