Alternative to discord: your best bet will be to find a matrix server at https://servers.joinmatrix.org. Element is the most mature client for all platforms.

For Facebook, any of the ActivityPub alternatives like Mastodon, Pleroma, GoToSocial... Too many choices for clients and instances, but if you are looking for a professional provider and care more about a "generic" instance that is well-maintained (or want to run your own), you can try communick. Disclosure, it's my own project and I've been running it for some years now.