I disagree, it’s definitely sketchy. Going out of your way to install the messaging host for a half dozen different Chromium forks is going out of your way do something behind the user’s back; it’s the opposite of lazy.
Another example is that macOS periodically sends records of which apps you’re opening to Apple, due to OCSP cert revocation checks: https://www.howtogeek.com/701176/does-apple-track-every-mac-app-you-run-ocsp-explained/
I realize this is ostensibly to enable a security feature, but if your threat model includes American software companies & oligarchs tracking what you do on your computer, it’s still something to be aware of.
I agree that this doesn’t rise to the level of “spyware,” but it is extra sneaky/slimy, and it absolutely, IMO, makes your system less secure for no good reason. They could just have a prompt in the UI the first time you attempt to use a feature that requires the native messaging host, which says something like “we need to install extra software to communicate with Chrome, OK?” This is the ethical thing to do.
It’s especially sketchy that they’re preemptively installing it in the right directories for multiple Chromium-based browsers, even ones that aren’t installed on your system.
That’s not really relevant to the point I’m making.