Of course this is possible if everybody else keeps their mitigations on.
If you have the spare cash and room, it's not a bad idea to keep gaming devices separate from work or personal devices.
Gaming may conflict with security in several aspects:
- Performance optimizations (eg. this website)
- Installing various closed-source drivers, peripheral utilities, or custom installers
- Granting privileged access to legitimate anti-cheat software
- Or even, perish the thought, installing pirated games and cracks
If you enable 2FA on your Steam account, backup your saved games to the cloud, and otherwise keep your gaming PC devoid of any remotely sensitive or valuable data, you can mostly have peace of mind as you blissfully install all kinds of untrusted software on what is essentially a glorified gaming console.
If you want to use your nice 38" curved monitor for non-gaming activities on a secure computer, a KVM switch is pretty cheap.
(Of course, if you're happy playing DRM-free games on Linux with a sufficiently powerful AMD card, you don't need to bother with any of that.)
mods are grate but many (not all) mods basically mean running programs with the same permissions as the game from not necessarily trusted sources
and while there are many trustable and reputable mods out there there have been multiple cases of high profile mods stealing user logins, e.g. in Minecraft.
For speakers you can just use a Y connector. Add a wireless mouse with multiple outputs built-in (eg Logitech MX Master), or a separate gaming mouse if you prefer, and that just leaves the keyboard to switch between the two devices.
Changing the input on my monitor requires three button presses, and comes with a noticeable lag. Then I've got to press a button on the bottom of my mouse, and another button for my keyboard. If I bought a fancy KVM, I'd be able to swap everything in a couple seconds! It'd be nice also to hook up a mic and webcam but I'll probably just think about it for another 6 months and never pull the trigger.