But Jaskier isn’t gay in the show, either. He’s bisexual.
Oh yeah, that completely changes things, and does completely fit in with the character.
I do have to admit that I did not watch the latest season, not because of Jaskier but because of what they did to Eskel in the previous season. So I took the other commenter’s word that the character was made gay. I guess that’s what I get for assuming honesty until proven differently on the Internet.