Making v6 a separate network from v4 was a mistake in hindsight. They needed to roll this out in steps, first one being you keep the same IP address and all except you're just using v6 instead of v4, with a NAT etc like before (which ofc you could turn off if you want). People only needed more addresses, not everything different.
You can't fit 128bit number in 32bit field. All suggestions I have seen are missing something or reinventing network address translation, poorly.
Expanding the address size did require a larger field but didn't require wiping out the existing addresses or anything else. We got the new packet header and near ubiquitous support for it, but that's not everything.
I made a deliberate choice to see if ipv6 was ready. I don't need ipv6, I do need ipv4. ipv6 doesn't work, ipv4 does.
The alternative (dual stack) is more work for no reason.
If ipv6 ever works then great.
I built a test ipv6 network for work but a lot of equipment simply didn't support it, and of that which did our suppliers said "well it might work but nobody actually uses it so we don't know"
It's a solution to a problem which was solved in a more backwards compatible way decades ago. It would be lovely if it worked, but it still doesn't.