Please do try running your own mail some time. It's not nearly as hard as doomers would have you think. And if you only receive, you don't have any problems at all.

At first, you can use it for less serious stuff until you see how much it works.

I do, I host my own mail server.

Technically it's not very challenging. The problem is the total dominance of a few actors and a lot of spammers.

I haven't had spam issues since using a catch-all and giving everyone a unique address, blocking ones that receive spam

Won't work if you need a fixed address on a business card or something, but in case you don't...

Waiting for the day they catch on. Then it's time for a challenge-response protocol I guess