It's from 2023 but the last Godot community survey showed a marketshare of 27% for Linux amongst the developer's primary development platform and 55% for exports to Linux[1]. That's quite massive compared to the 2.06% Linux and 1.4% OSX have amongst gamers[2]. So, if you need help getting your game to those 3.4%, there should be plenty of helping developers on the usual godot forums.

[1] https://docs.google.com/forms/d/e/1FAIpQLSeXRE1nF64PUilO6fA7... [2] https://store.steampowered.com/hwsurvey/Steam-Hardware-Softw...