I disagree. They do incorporate plenty of feedback. A big example of this was/is FCPX... the ********* after FCPX was first released in 2011 caused Apple to backtrack on a lot of removed features, etc.
They also accepted feature requests on the old bugreport.apple.com interface, and I'm sure they do in the current Feedback application.
i'm sure, as soon as apple reads your post, that coverflow will return.
seriously, if
many FCPX users complained (a pro app for a much-smaller group than
all macusers), it's not surprising that apple listened. but what percentage of ALL macusers are clamoring for coverflow? 1%? more? less? even here on this forum, there's far more discussion about dashboard (which also won't be back).
still, anything is possible, an no one on this forum (including me), can predict what apple will/won't do.