In Poland, Play.pl sets up IPv6 by default. One phone call to ISP to disable the hidden firewall on their router gives us full IPv6 network transparency, no NATs are needed anymore. I highly recommend after installing a firewall appliance (for example OPNsense, but probably Mikrotik should have it as well). IPv6 "feels" like how networks should work since the beginning. IPv4 feels like a legacy technology.

They of course also have a DS-Lite AFTR gateways to tunnel the IPv4 traffic. In practice, everything works (for me at least).