when they asked permissions?

Immutable distro debian based with GNOME

Probably the fact that they have many ISOs tailored for each supported hardware configuration, and they point the user to the right ISO with a clear wizard in their download page.

Also basically it is an unbreakable gaming focused OS very close to SteamOS, that you don’t have to maintain, and it comes preconfigured with Steam and the right drivers for your setup. I’m not the target audience, but I see the appeal.

You should be fine. Linux and BSD systems have te ability to load microcode updates at boot even if you don’t update your BIOS.

I’d be more concerned about the noise and power consumption.

Also the number and the max speed of your NIC is a factor if you have a fast internet connection If you run OPNSense make sure your NIC is well supported (I had problems with realtek and paravirtualized cards). Otherwise you can always add more NICs with pcie cards.