There is this attitude that, unless the Art (or Craft) has a steep learning curve, that
a) it is "cheating", or
b) it is only for children (and therefore adults should be publicly mocked and shamed for doing it), or
c) it isn't possible for someone to become skillful at it because there is no skill involved in it whatsoever
Yes, I'm thinking of Acrylic Pouring in particular, but it isn't the only one.