No problems here with AT&T fiber. Yes, you do need their box (the bypass isn't even possible yet on their new model that they seem to be installing everywhere now). But the IP passthrough works well enough for me so that my router gets the public IP and I can connect to it using any service I've tried to host. I make the best of it by using their wifi (which on the BGW320 is pretty decent) for untrusted devices & iot stuff.
Oh, and I use DDNS, but I have never had the public IP change on me.
https://support.google.com/fiber/answer/6149458?hl=en
Basically it's fine but they also offer static ips.
Zero issues (other than an IPv6 annoyance—see below) for me running a homelab with Google Fiber.
I switched from ATT Fiber because I really hated using their box (I bypassed it with an EAP proxy but it was brittle and it still had to be plugged in). Google Fiber doesn’t require that so you can plug your own router directly into the ONT.
I’ve had the same IPv4 address since I signed up, but IPv6 prefixes do seem to change every so often (which is baffling to me—seems like it’d be easier to leave the IPv6 prefixes alone vs keeping a static IPv4).