Even if Firefox falls by the wayside and websites stop working with it somehow, making Blink (and Webkit) a monopoly (which I think is a very important thing to

Even if Firefox falls by the wayside and websites stop working with it somehow, making Blink (and Webkit) a monopoly (which I think is a very important thing to prevent and is the reason I use Firefox even if I don't have the warmest feelings toward Mozilla), I don't think that the free sync API being removed means that everyone will have to use Google Chrome. The major Chromium projects—Brave, Vivaldi, and Edge—all already use their own sync engines independent of Google.