People like to shit on Telefonica/o2, and after half a year of trying to get my bills corrected I can see why. But I've had dual stack on my DSL for several years now without issue (caused by them).

Giving you a dual stack IPv4/6 address (with IPv4 often NATed) is one of the thinks the German ISPs do well.

But for many other thinks there are to often to many problems including bad availability of speeds about 50Mb/10Mb and they still selling you faster speeds which technically can't be delivered.

And for many areas of Germany it boils down to:

- If you live in a city and only go for 50Mb it's often ok (but even in cities there tend to be areas with faulty installations causing problems for the citizens in that area for years, e.g. my sister and a co-worker of mine had/have that problem).

- If you live in the metro area but not in the city it's spotty sometimes going with LTE is better, sometimes it's not, sometimes you should by both to make sure at least one of them works (my former co-worker had that problem).

- If you live outside the metro area it's random either you get reliable reasonable fast internet if you buy from the right provider or you get less then 1Mb no matter what provider you choose (multiple of my friends had/have that problem).

I also remember having IPv6 in Germany for years now, but it came with lots of problems: routers cannot forward things properly, thus self-hosting at home becomes tricky, or playing games with friends without dedicated servers (yes, they still exist, no, not all support IPv6). It gets even worse with "DS-Lite", where multiple customers share the same external IPv4 address, to enable support for all the webservices not supporting IPv6 yet.

All in all, I had so many troubles with setting up anything behind IPv6 or DS-lite, that I asked my ISP to give me an additional IPv4 address, so that I don't have troubles. While they usually provide bad service, this came for free -- but other ISPs, for example my parents' ISP, want you to pay 50 or more euros per month for an "enterprise contract" to get a dedicated IPv4. I still haven't found a way for my dad to setup his old webcam server at home such that others can reach it from the outside world, and I tried every couple months over the last 6 years or so.

I have a Vodafone cable in Berlin and it gives you one ipv6 address in NAT mode. Not really helping if using your own router and needing more than one ipv6 address (that is typically the case).

I do VPN from the router, giving me a proper /64 block...

Yeah since moving to Germany in 2016 I've been getting IPv4 & IPv6 addresses (on 1&1 / Versatel). Was very surprised when first noticing it!