I agree with you, harsh and unobstructed criticism is of paramount importance.
Even if it's just an opinion (what the hell, of course it's gonna be an opinion, most things we say are opinions).
Even if the artist gets offended because his ego can't handle it (which is very, very often the case).
In the end, harsh criticism helps everyone in the long run.
Unfortunately such criticism is rare in fora like here, where people are eponymous and interact with each other daily, and the social norms of friendly behaviour take over honest critique.
But it is what it is.
Anyway, what I totally disagree with is removing (=censoring) a photo, against the photographer's will, because someone "got offended".
Getting offended is a personal matter than one should resolve himself, facing his inner demons and insecurities.
Getting offended is a ridiculous reason to censor others.
I can't force the Muslim girl walking next to me to take off her burqa because I "get offended".
I can't stop the Christian lady in the tube murmuring a chant because I'm an atheist and "get offended".
I can't force the gay couple next door from kissing in front of me, because I'm heterosexual and "get offended".
Why should I be able to force someone to remove their artwork because I "get offended"?
"Getting offended" is a buzzword to enable people to essentially censor what they don't like and limit the freedoms of others.