While I agree with your sentiment--that design by consensus and indecisive design are bad--I'm not convinced that including a feedback button is a bad thing. I

While I agree with your sentiment--that design by consensus and indecisive design are bad--I'm not convinced that including a feedback button is a bad thing. If it's well-placed and unobtrusive (doesn't flash "what do you think of our redesign?!") a feedback button serves the purpose of providing a bit more information about user pain-points. Keeping in mind that most users have too much inertia to hit a feedback button, when it is used you get reports of major frustrations. That could be a bug in a corner-case or browser you didn't test, or an accessibility issue. So, I'd argue that quietly keeping a feedback button around is a good thing, and as developers it would be our responsibility to handle the feedback responsibly (filtering noise, distractions and unfixables).