In the world of computers, why would remembering numbers be the stop for new technologies?
Do you remember anyone’s public key? Certificate?
I don’t even remember domain (most) names, just Google them or save them as bookmarks or something.
The reason IPv4 still exists is because ISPs benefit from its scarcity. Big ISPs already paid a lot of money to own IPv4 addresses, if they switched to IPv6 that investnywould be worthless.
Try selling static IPv6 addresses as they do now with IPv4. People would laugh at them and just get a free IPv6 address from an ISP that wants to get new users and doesn’t charge for it.
The longer ISPs delay the adoption of IPv6, the longer they can milk IPv4 scarcity.