It sure would be convenient if retailers like GoG had awesome controlled support for various and sundry Linux distros, and for MacOS, and for the TRS-80 Model III and the Amiga 500, but:

What does a person buy when they buy a game from GoG?

In my own experience with buying from GoG: What I buy is a copy of a Windows installer, and [often] a Steam code.

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If I then want to do something on my Linux box (or my Amiga 500) with that Windows installer, then: That's on me.

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I don't think that they owe me anything else here. YMMV.