[exfascist]

Comcast in the US does (if you use your own router and configure it correctly.)

There's this goofy band of people that know just enough to bring their own router but don't understand why a misconfigured AAAA record can mess up the happy eyeballs algorithm and are convinced Comcast is "censoring" small business. It's funny and kind of sad to read comments from people who are certain their misconfigured networks are the result of some "international conspiracy" against them. That's probably why Comcast has it turned off on the routers they loan to customers.

[johnvaluk]

Comcast Business requires customers to use a gateway provided by Comcast to support static IP addresses. I was thrilled to finally get IPv6 support, but it seemed impossible to prevent Comcast from inserting their own nameserver in IPv6 leases, which broke my network. I tried running my own dhcpdv6 and radvd servers to no avail. This took me way out of my comfort zone and much deeper into the weeds of IPv6 than I ever expected to go. I finally disabled IPv6 (and I can't even tell you how I did it) to get things working properly again. Maybe I don't have the required skillset to implement IPv6 properly, but I really got the feeling that Comcast introduces unnecessary obstacles for business customers with slightly advanced needs in order to serve the lowest common denominator (aside from my special requirements, IPv6 mostly worked out of the box, which is probably their goal).

[xoa]

Seconding this. It's a very irritating implementation detail of Comcast Business service. It can be worked around of course, if you have a VPS somewhere close-ish with a static IP you can do the whole WireGuard tunnel thing at the cost of some extra moving parts and maybe a minor latency hit. And while overall their business offering is certainly vastly better than their consumer shit, if you're on their router they're still jerks. I've noticed their own pushed WiFi keeps switching itself back on for example. Overall it reinforced my desire to use absolutely anything but Comcast whenever possible, though when it's not I'd still pick business service of consumer service.

[BlueTemplar]

Yeah, that has been typically the case a few years ago around here - you could have more than a single /64 on a residential connection (and better than the bare minimum of other IPv6 functionality), but it required to get your own router (and sometimes even spend time with tech support because they wouldn't test that use case as much as their own router that you'd get by default).