IPv6 after so many years still is a victim of the chicken-egg-problem. People don't need it because services don't support it because people don't need it because ... and so on and so forth. I try to enable IPv6 wherever I can and I didn't have a propblem for ages. Dual stack is stable and there are actually a good amount of services that support it.
I think we should all push to implement IPv6 so that IPv4 can finally be laid to rest. Using IPv4 makes everything a bit more expensive because it is so damn expensive to get a stupid number. If someone is really scared that every computer has a publicly routable IP, and if you really think you can not configure a firewall, there is a private IPv6 space and you can use NAT with IPv6. It's not recomended but it's possible. I'd still say using a firewall is not harder and just as safe.
And there is the fact that you can make so many subnets which can make your internal network so much safer. You can controll better how packages are sent to groups because broadcast was dropped in favor of multicast. There is IPSec Support built in. Secure Neighbor Desicorvery to prevent attacks like ARP spoofing. There are a lot of reasons to implement IPv6 and even to switch to IPv6 only if possible.
You can transition step by step. Dual Stack is a thing.
That makes no sense to me. Every network in itself doesn't need IPv6. The 10.0.0.0/8 range has 16 777 216 addresses. IPv6 only makes sense if everyone uses it. We bought ourselves time with NAT and CGNAT and splitting up older ranges but that won't last forever and is costly.
Everyone needs to transition otherwise services will need to keep their IPv4 forever. And if the services keep their IPv4 users don't have an incentive. Maybe we should transition BEFORE there is time pressure. Now is the time to slowly start setting everything up with enough time to plan and test firewall rules and appliances and everything else.