Imagine if Microsoft did this on PCs. a) prohibiting the installation of non-windows store software (sideloading) and b) insisting that all purchases done via apps give them a 30% cut. I think this is a ridiculous practice on the behalf of Apple.

Even worse. Imagine if the World Wide Web was not open and you had to go through a closed WWW like AOL and websites were "under review" by the providers and would take a 30% cut of your revenues or clicks on your web app or subscription service and websites require going only through that provider.

Thank goodness that wasn't the case.

It could be the case if AMP grows dominant; given the market share of Google Search, it could be enough to create a controlled (er, "curated") web in a similar spirit.

We're closer than we have been in a long time to something like Google deciding to license Blink or Chromium. There are some good reasons that couldn't happen (yet), but what a world that would be.

I can't picture this happening due to the sheer size of the Electron ecosystem. Do you think there's any precedent for this?

Is there any reason Electron couldn’t switch to, say, Firefox?

Electron is really 100% Chromium. I can't see them switching from it (though it would be nice to have a Firefox-base version).