I wonder how much longer we'll even have the option to use our own equipment. Late last year I briefly tried AT&T fiber, and it was required to use their hybrid modem/router monstrosity. It didn't even have options to disable the router functionality, the best you could do was turn off its WiFi networks and disable its firewall. Even after setting all of my own passwords on it it was still possible to access settings through my AT&T account online, telling me that the thing is backdoored all to hell. TBH that thing was a big factor in me canceling the service after 5 days (also the service was mediocre and they tried to screw me on pricing).

You can bypass the AT&T RG:

https://github.com/jaysoffian/eap_proxy/

That said, I haven’t had any trouble with it as a router.