2024 is the Year of Linux on the Desktop, at least for my boyfriend. He's running Windows 7 right now, so I'll be switching him to Ubuntu in a few days. Ubuntu was chosen because Proton is officially supported in Ubuntu.
It's ancient, unsupported, and closed source. Nobody can create or distribute security updates. People would have been happy to keep using horses and buggies if there'd been an automatic horse shit shoveller.
That's true, but their apathy or ignorance is a threat to any networked device. There's definitely an argument for "my device,y software, my rules", and technically you can run windows 7 as long as you want, but Valve shouldn't be perpetually expected to support deprecated software either. In their case specifically, if would be hard to ensure their anti-cheating software isn't being circumvented at the operating system level, meaning the experience of everyone on any OS would be lowered by continuing to support a 14 year old version of Windows.
How so? 7 is the last good version of Windows. It's not surprising some people want to keep using it. It does have security issues but at least there are no ads in the Start menu and it doesn't shill for OneDrive on startup.