I have been in a different open source ecosystem where one company totally dominated the foundation (in different ways). The result of that is that everybody had to go through the long process of open source to get things to evolve (and many times the answer would be "we can't have what you want because it would break stuff for others"), but that one company could just silently push what they needed (and if asked they would always find "good reasons" why it was for the good of the community, which was really not clear at all).

In the end, it feels a bit like Google with AOSP or Chromium. Yes it's open source, in the sense that you can fork the code. But for the better or worse, it's not open governance. Matrix advertising itself as the "free" messaging protocol means that having one company dominating it is not a great thing, I guess?