That's a good point. Indeed, in a vacuum world it would be very much a problem that needs to be addressed. Right now however, there are ipv6 addresses in use that use the other end of the spectrum already. During the migration period it won't be a problem either. In the far future, where most traffic uses the new scheme, one can hand out temporary ranges from the traditional ipv6 assignments to high-traffic ASs.

And even if you don't do such measures, the rest of the address space won't be a "complete waste forever", one will just have to identify the implementations which have problems with these addresses and change them. It's a solvable technical task like any other.