Re Google Safe Browsing
I would argue it’s a security feature with potential privacy concerns, however I would agree it is more of a failsafe or suggestion.
However it being disabled by default or not included at compile time versus enabled by default may also be relevant when it comes to security. As a hypothetical a high severity bug with Google Safe Browsing could arguably make a browser less secure. However even as a failsafe/suggestion, the small security benefit may make the overall browser more secure, e.g. filtering known bad websites that attack known vulnerabilities.
I’m also just using Safe Browsing as an example here, it may or may not be worth focusing on since a browser is basically an operating system.
You mentioned sandboxing, which I think is perhaps a more reasonable scope.
That’s the only conclusion I would have trusted. Otherwise you should have been awarded the tech equivalent of a Nobel Prize.
Security (and privacy) is not a zero sum game. That isn’t to say we shouldn’t discuss it. That isn’t to say we can’t point out clear advantages.
In any case, I appreciate the write up.