To what end though? 4 billion addresses is not enough on its own, even if they were reallocated from hoarders. I think that NAT and especially CGNAT have been very detrimental to the shape of the internet, where it's nearly impossible to self-host a public service without a VPN of some kind. Needing to pay some company for the ability to host a server that isn't behind NAT is a barrier that doesn't need to exist when IPv6 has a nearly limitless number of addresses.