> Likewise, with the GUI software I'm writing, 'Defining Linux support' is something that is not worth doing given that there are tons of distros out there and by selecting one or two distro's there will always be an endless amount of people asking to support X distro or Y distro.

There was a major game developer (sadly forgetting the name) who decided to support Linux as a test around 2018ish. The Linux users were only a few percent of their users but ~20% of the support tickets. They said never again.