I'm with you. but matrix is failing adoption for the same-ish reason as PGP.
You create an account from scratch, means using two (three) centralized services. matrix.org. vertex.org. (and the third is possible your email provider which would be either gmail.com or icloud.com)
Then you get a password, recovery keys, recovery passphrase, session keys. And have to know what to do with them all.
Not sure how it improved on v2, but recently i had friends doing literal PhD on cryptography code having to create a new account because they forgot to save one of those keys when replacing phones.
The reality is that worst case, it should feel like a laptop (username, password (unless using SSO) + recovery key) or a cryptocurrency wallet.
With the v2 crypto, you typically don't have to remember anything - you just scan a QR code to log in.
If you've logged out all of your devices then yes, you need username + password (unless using SSO), and then if you want to recover your encrypted history you need the recovery key.
It's true that the UX historically was awful, but on Element X i believe we've got it right (and Element Web/Desktop will shortly follow).
Unless your data should be on your server, in this case yes you have to launch your own instance.
Once you're logged in, there is a "+" sign on the left. Create a public or private space and then add channels to it.