Dusk: Unpopular opinion: I'd rather pay Valve 30% and put up with their de facto monopoly than help Epic work towards their own (very obviously desired) monopoly
I will always support valve because of their amazing Linux support but if GOG finally made a client for Linux then I would try to use that more. I wish Epic would also support Linux but with massive douchebag Tim Sweeney running the company, that will never happen.
If these platforms supported Linux, they'd be able to compete with Steam... 15 years ago.
Nowadays Steam offers so many solutions to PC gaming that other clients simply would take ages to copy. Steam Input, cloud saves that actually work, Steam Link, Remote Play Together, etc