I think we're much smarter than we were. Everybody knows that abstract art can be art, and most people know that they may not like it, even if they understand there's another purpose to it.

This quote is saying that people in general are more knowledgeable and better educated than they were in the past. For example, most people now understand that abstract art can be considered art, even if they don’t personally like it or understand its purpose. This shows that people are smarter than they used to be, because they are more aware of different types of art and can recognize its significance.