There have been various alternative suggestions posted.

Sitges
I've been there several times, although never for holiday. Whilst the party scene is good, all the guys on Grindr are big and hairy. Not my type at all. Also it's likely to be cold in December.

Tokyo
A very interesting city, with a lively gay scene and cute guys. To actually get one in bed requires either searching for one who likes a mature westerner, or paying out considerably more than in Thailand. If the latter, good service is assured.

Singapore
The naked night at the sauna almost justifies the trip on it's own. If such places are allowed to open with COVID. After that, finding a cute and willing boy can be much harder work than in Thailand.

Also, in all 3 of these locations, living is far more expensive than Thailand. If I had to choose one of these 3 for the gay scene, it would be Tokyo.