it's a question of tooling, modding kits

most times it this tooling which causes issues not the mod itself

For very popular games it's not rare if moddingkit/tooling producer (or contributes) made the tooling work on Linux, but it can be very hit or miss.

but it increasingly more "just works", kinda, somewhat

Yeah. I recently tried to run an auxiliary program (Mass Effect save editor because the character creator sucks) on Linux which was only written for Windows. Getting it running in the same Proton "space" (bottle?) was not an enormous challenge, but it was very far from "just works".