We have a Thai Airways direct flight from Brussels to Bangkok, but I don't like that airline.
The best, but often the most expensive solution, is Emirates.
I like Austrian Airlines and Turkish Airlines.
Lufthansa did not so good service.
I'm from Belgium too.
The prices of plane tickets to Thailand have doubled compared with 2019. I don't notice much difference in hotel prices.
Prices for special services in Thailand are still very reasonable, and inflation of prices in Thailand is lower then inflation of prices in Europe.