As far as I know, Matrix wants to do something similar to this. They want user IDs to be public keys. A user ID can be bound to a name, but can change the name over time and keep your connections.

I'd say the big problem at the moment is that people are not used to paying for service. Lots of stuff related to naming is very cheap. But if you require it to be free, then you will get bad incentives like trying to build a silo and fill that silo with ads.

Would it be a thing that ISPs could manage/charge users for?

That way, users ARE paying for it. And honestly, it is a fundamental internet service, just not in the way most people think of.

LDAP could have been that service - a distributed directory. I'm not sure why it didn't become universal.

OpenLDAP's a bugger to configure, and it's much more than you need for a simple directory. But ActiveDirectory is nearly omnipresent.

as soon as you create a namespace like that, you've made the lever that will be utilized for centralized control. In reality, if you had no chance of getting somewhere without the centralized registry, you don't have the connection.

What I am proposing is an extension to DNS to allow individuals to find each other directly rather than having to go through middlemen like FB etc to simply message each other.

DNS already exists as a point of centralised control. Service Providers already have to log IP vs user accounts.

don't see how extending DNS for the masses could make things any worse.

As a sibling comment points out though, who pays to run it?

Don't Tor onion services basically work like that already?