Thanks to all of Valve's effort with Proton, Steam Deck and their funding of people working on various other bits of Linux code like GPU drivers - the Linux share on Steam as of March 2024 bounced back to a near multi-year high.
But yes: Selection is random. And since Linux users still make a small perecentage of Steam users it can make a huge difference when the randomizer selects fewwer Linux gamers.