Absolutely! You don’t get the former (keys) because you can’t get the later (secure render stack) as a “normal” Linux user.
That said, one thing you got technically(!!) wrong:
You can get a secured (stack) and certified (keys) Linux, if you close it up properly… Source: I worked a little bit on one of those, and yes, I’m ashamed, and yes, I’m expecting a bit of hell time for it… Was a fun task though.
Warframe might be for you.
You can play everything solo, or join with random people without the need to ever talk to anyone.
After a while, if you feel like it, you can use the in-game chat, or not. You can join a clan, or not (not being in a clan has it’s downside though, nothing critical except the arch wing, which must suck not having)