I would never use an ISPs router for my home network. It just causes so many issues that you can easily avoid by either using your own router directly or if that is not possible putting the device into “bridge” mode and using your own router behind it.
What are some of the issues?
The devices the ISPs send out are usually the cheapest hardware imaginable and therefore introduce substantial unnecessary latency.
Where I live some ISPs also used to use tools that genereted wifi passwords based on the devices MAC address. While this is apparently fixed now, a lot of non tech savvy users still use these old devices that are basically open to anyone now.
To save even more money, they sometimes deliberately send out faulty devices (as in devices that drop connection frequently, restart for no reason, etc) which is just horrible.
I know these issues because I worked in that field and there are a lot more unfortunately…
I was in the same boat as you a year ago, but Windows got so bad that I just accepted that I could only play 90% of the games I want and had to check protondb before buying a game.
Also I wouldn’t use a distro that has GNOME as their default DE. KDE is (currently) superior in many ways that matter for gamers.