These commercial, proprietary games are one of the things that pushes forward the capabilities of personal computers. They are unreasonable, unoptimized resource-hogs. If a Linux system is as capable of running them as a proprietary OS (that has a deck stacked in it's favor), it means they lose one another advantage over Linux. And it also means that your hardware now is more productive at less bs tasks, especially consumer-grade nvidia cards, who are better supported now than years ago.
If you are a Linux user and like commercial games, you probably would prefer them to work on Linux.
“Market share” on Linux aligns the vested interest of game makers and Linux game players. If the company thinks it can make money, it will do more to allow games to run, or at least do less to stop them.
What would be great is they'd likely need to open source certain stuff for it to play nice with the kernel. Stuff like DirectX. And if that happens it'll be a singularity moment for Linux compatibility and adoption.
There's high potential overlap between the profile of a PC gamer (who is often also a PC builder and general computing DIY hobbyist) and an OS like Linux that extends your tinkering ability massively on the software side.
PC/laptop users are a shrinking demographic nowadays thanks to the advent of mobile devices, but they're a high quality demographic made up of professionals and hobbyists with above average computer savvy. So lots of companies are trying to appeal to them because the choices they make in software and hardware can translate into many other IT fields.
I have at least 20 different devices that run some flavor of Linux. Servers, a laptop, TVs, AP/routers, probably more, if my other "smart" appliances run Linux also.
Do Android phones and tablets count towards Linux gaming?
PlayStations run a derivitive of BSD, maybe those should get honorable mention. ;)
Including phones would be significant. But in my (probably deranged) head android/linux is a different os from GNU/linux. The overlap of the kernel itself is not enough. In that case all switches/routers/storage appliances/toasters/washing machines/fridges/iot sensors often also run linux.