Mac gaming is an extremely interesting phenomenon: there's Epic Games (official client, native), GOG Galaxy (official client, native) with games like Control, Cyberpunk, and Baldur's Gate III (the latter was even requested by Oprah Winfrey), and an audience that can be counted on the fingers of one hand.
Here, Linux gaming is a more interesting story: the audience is 1,5-2x larger1, 27,000 games among the verified ones (including native ones)2, and no official clients, but a sea of ​​unofficial ones, such as Heroic, Minigalaxy, Lutris, the defunct GameHub, and a huge number of gaming tools like MangoHUD, Piper, Oversteer, etc.
It's surprising that Epic Online Services fully supports Linux; the client is written in Electron, and it would seem there are no obstacles to porting other than the developers' desire.
GOG is in a similar situation, the only difference being that they already have a complete, albeit incomplete, catalog of games for Linux, and the GOG Galaxy API hasn't been ported to Linux (third-party clients use the open-source Comet implementation).
Therefore, the question is more rhetorical: wouldn't it be easier to port games and clients to Linux if they have a larger audience? This audience is often directly involved in the IT industry and, for the same reason, is just as wealthy as Apple fans.
Whitelist of games for the Steam Deck, we proceed from the simple intention that any game that can run on the Steam Deck will also work for desktop Linux https://www.protondb.com/explore?selectedFilters=whitelisted