Some implementations not implementing all the XEPs is exactly my point. "A Matrix server" / "a Matrix client" conveys an expectation that certain functionality will be included. Low-feature implementations will exist, but I assume it will be clear they serve a niche.
Synapse is the only fully featured server. Element Web/Desktop is the only fully featured client. Most of the other servers and clients are aiming for general use. They're just incomplete. Some of the niche implementations like weechat-matrix are in better shape actually.[1]
