When I worked at Google the efforts to port Chromium over were seemingly tied in large part to needing to have parts of it to get the Chromecast ecosystem runni

When I worked at Google the efforts to port Chromium over were seemingly tied in large part to needing to have parts of it to get the Chromecast ecosystem running on it. Because the devices they were targeting for Fuchsia to use were built on top of that. (though a lot of that UI also got rewritten in Dart/Flutter instead, so) I wasn't directly involved but was a tiny bit of a voyeur. I seem to recall (this was 3-4-5 years ago) that there was a lot of push to try to componentize things in a more Fuchsia-ish way, but this naturally ran up against the realities of how huge and big the Chrome codebase is. And Chrome has its own IPC system (mojo) and its own component model(s), its own threading system, etc. and assumes POSIX stuff throughout, etc. My suspicion at the time was that as something like Chromium gets ported to Fuchsia the result will be less that Chrome becomes friendly to Fuchsia, as much as that Fuchsia becomes less distinct, and more a "typical" OS, out of pragmatism. I dunno, I'm curious to see how that effort is going. But I think it accords with your point. Porting big applications to "alternative" operating systems with more interesting or exotic models... you either end up losing the OS's distinctiveness (in which case why not just run in a VM), or having to rewrite a lot from scratch.