There should not be any curbs on artistic freedom so long as artistic freedom does not entail physical harm to human beings (or their property) or cruelty to animals.
One of the hallmarks of an advanced democratic society is that it can handle the expression of distasteful ideas. A democratic society does not react violently to offensive depictions of its religious figures. It can look at such "art" and simply shrug it off.
There is no real good that can come of curbing artistic expression. Whenever we say that some ideas or some ways of expressing ideas are unacceptable, we put ourselves on the proverbial "slippery slope." We start to have problems drawing the line in ways that prevent us from censoring people's ideas and imposing one set of moral and political ideas on all people.
Therefore, I see no good reason to curb artistic expression unless it causes actual harm to living things or to property.