I sometimes watch the flights to/from BKK airport on FlightRadar24 or RadarBox, pretty cool sites.
If you are up early (5-7am or so), you can see the Thair Airways flights coming in.
They come from various places, but are lined up back to back (synchronized) coming in. Obviously I cant speak for the Profitability and Airline business, but to me, thats a good sign that its not just random Thai Airways flights coming in.
That has to be a purposely thought out scheduling. So that to me shows TA is doing something to keep costs down. Obviously to have Check-in, welcome Gate, Baggage people all working continously and not stop-start (inefficient).
So to hear them making money, is just reward for being pro-active and working to optimize Flights. Its a different world now with the technology out there.
There are even specialized Apps of the ones we use, like Waze, TomTom and such.. that UPS and Delivery Companies are using tweaking delivery drops to where fewer Left/Right turns (depending on Country) are done.
Also, many top routes of BKK are Domestic, so TA will benefit as those tend to be pretty profitable for a lot of Airlines.
https://www.flightradar24.com/data/airports/bkk
Wish them continued success.