Isn't the point to play games and being able to login to most sites these days?

It also gives you backup internet..

Not really, not for me and many others anyway. I would just get an LTE modem for backup internet, my PC is better at everything else. I'm not sure about which sites you're talking about, but you can also do 2FA without a phone.

There are a ton of big companies and even governments that only do SMS 2FA. The US social security website is one of them.