You don't need to. This is no different than how lack of SNI is handled with IPv4, just have multiple static IP addresses on whatever frontend you're using. With IPv6 it's easy to delegate as many IP addresses as you want. The slight problem with this is that it doesn't solve the privacy problem at all as now you just look at the IP address and check which domain it serves.

If thats true it’s because of the limitations of IPv4 more than anything else. With a single $5/month machine from Linode you have a /64 IPv6 subnet, that is 2^64 IP addresses just for that one machine.