4 pane comic of dolan on the left and spooderman on the right
pane 1 (dolan): cum join opensurce cummunity!
pane 2 (spooderman): shure! how joyn?
pane 3 (dolan): Here discord! (with discord logo)
pane 4 (spooderman with tears in eyes): y u do dis?
Element is just a client, while Matrix is the chat protocol. But yeah, I have recently switched my discord server to a matrix instance and its been pretty great. Some pushback by users who didn't care about privacy or security, but overall the tech is solid. We didn't like that discord was moderating private chats and they don't offer any type of encryption.
I think the point here is that anything that can be indexed by search engines or archival crawlers would be better, so not Matrix either. Forums, for example. Like what happens if the Discord community gets deleted due to whatever circumstances? All of that gathered knowledge will be just gone with no way to recover or search for it.