From a business perspective, data sovereignty and end-to-end encryption seem to be really potent differentiators for certain market segments, especially government. To wit, the French government has a massive Matrix deployment under the name "Tchap", and the German military began rolling out a similar initiative called "BwMessenger" last month: https://esut.de/en/2020/11/meldungen/24138/matrix-messenger-...
On the opposite end of the spectrum you've got Mozilla, who replaced their IRC network with open, federated Matrix and saw greater far greater community engagement as a result.
October also saw a commercial entity (Famedly.com) begin sponsoring the development of a third-party homeserver implemented in Rust (Conduit). So we're starting to see glimmers of a potential ecosystem around the Matrix protocol independent of Element.
We don't have the same pop culture buzz as Slack or Discord, but I absolutely think there is something of substance here.