This reads like the Show HN: Dropbox thread; UI/UX for Mumble is typical of engineer-design. Setting up a client as a user and being told to set up client certificates for mTLS and export your certificates with a strong passphrase to not lose access to your server is an insanely high bar for casual gamers, though a lot more secure.
The mumble wiki literally has the sentence "For more information about certificates, see the Wikipedia entries on Public key Certificates."; PKI is barely well understood by many engineers. The last time I used it, setup also suggested that instead of a self-signed cert, you got an email-verified mail signing certificate from an actual CA.
For comparison, Ventrilo and Teamspeak are heavily DRM encumbered, your servers go offline randomly when the licencing servers go down due to frequent attacks as they phone home and get no response, have utterly insane ToS that near totally shuts down community servers [you aren't permitted to run your own, Ventrilo will not even sell you a personal licence, TeamSpeak shut down their non profit licence thing and revoked all of them], forbid you from self hosting on your own infrastructure and tell you to buy from their 'hosting partners paying per slot', but you just get an admin password at first start of the daemon.