In my mind, good criticism isn't a heavy gate which requires a good deal of force to open and whose posts run deep and sturdy into a bedrock of accumulated "facts" and knowledge. Criticism is much more dynamic that that, a place that could be an entry but may not be, and, at its best, criticism takes on some of the untrustworthy and "useless" qualities of artistic work.
To me an excellent and honest "critique" expresses one individual's experience of interacting with a work -- listening, reading, viewing -- and any explication it offers grows from this remaining true to the individual's experience. If I did not think "critical writing" offered those freedoms -- one of which is the freedom to be who you are, whether that is an amateur, a simple fan, a practicing musician, a scholar, someone with an axe to grind, whatever -- I wouldn't even bother with it.