What do you find so problematic with tor?

I've been using another chat app that uses tor (briar) to chat with my family and the chatting app has been working flawlessly for us so far.

Tor curcomvents the nonsensical restrictions that isps place on users and makes it very easy to build p2p applications. No need for stuff like nat stun turn. Just exchange public keys and go!

If anything, I find it weird that other p2p chat apps don't use tor given how easy and reliable it makes the chatting UX.