Are IPv6 numbers not available from your local registry at low or no cost? Or in these late days must you rent them? Or is this just a problem of people not wanting or knowing how to run BGP so they can control their own fate?
Run BGP... with whom ? Let's say I have my own AS and a prefix given to me, which is indeed quite open and not too costly. If my ISP coming to my facility won't allow me to set a PTR record, they for sure won't allow me to run BGP session with them !
There are VPS providers out there (like Vultr) that offer BGP. You can either use the IPs on their cloud instances, or tunnel IPs back to your home network, etc.
Vultr is actually really awesome. (And highly unusual in their BGP support!)
You're supposed to get your IPv6 prefix from your ISP's allocation, not directly from the regional registry. Simplifying the routing tables with hierarchical address assignment was one of the major selling points for the larger address size in IPv6. If everyone gets their own prefix independent from their ISP then the core Internet routing tables will continue to grow ever more complicated.