I hope so, browser monoculture is really scary, imagine everyone with the same browser with the same security bugs and no way to use something else.
Having been using Firefox and Chrome side by side for 10+ years, I don't think the difference (or preference) between the two worth the effort putting into making two (mostly) duplicate implementations of the same thing for such complex thing. And my experience in observing the development of Firefox is that they are already too short-handed to keep up.
Keep in mind Blink engine is forked from WebKit (an Apple product) and Chromium is created from thin air. Yet it doesn't stop Google to have the dominant position they have today.
My point is, Google controlling everything is bad, but having only one engine (be it chromium or something else) isn't what causes it.
Also, I don't say "should", I say I don't mind.