Those companies aren’t polluting for fun, are they? If nobody buys their products, no pollution is done.
Of course, a valid counterargument is that buying alternatives is too expensive (or non-existent, which most likely also has to do with price). And then the valid recourse is politics, subsidising alternatives, or in my opinion the better choice: making polluting products more expensive (by means of carbon tax or cap and trade).
Is their shift key broken?
Furthermore, this blog post has outdated information and many of their problems with Matrix are fundamental for federated protocols. Good luck removing an email sent to another server, for example. JSON form is very well defined.
I can agree with the problem of DAG complexity building up, sure, but that is a tradeoff.