I had read that that's not really true, here on HN. I think the thing is that FF refuses to implement some things they think would be bad for security and privacy. They are not saying no to all PWAs. Chrome on the other hand doesn't give a damn and is trying to make the browser an OS.

Take a look at 'encrypted client hello' on FF. I'm on FF Beta android, which supports 'about:config'. Now I can access many blocked sites because of the ECH.

That argument doesn't really apply very well to the linked bug.

This was about removing the feature (which IIRC wasn't completed yet) that would allow you to "install" a PWA. I'm as disappointed as you that they removed it, but calling it "they removed PWAs" is just FUD.