I think this is a n interesting topic, which has far more nuances than at first glance.
I admire Banksy's work, and I don't think I'm aware of any with which I disagree politically, but that has to be balanced with the fact that the law has to be for everyone (despite the example set by the current government). Rule by consent is seriously compromised if laws are applied to some and not others.
Also, as was said upthread, I know I would feel differently if racists, homophobes or incels expressed their beliefs in art and inflicted them on the public, however talented they may be. Talent is not a free pass to be above the law.
Plus, what some find beautiful others find hideous, and there is the question of ownership of space. I might not mind if someone like Banksy painted on the side of my house, but I wouldn't be happy with crowds there all day taking photos, and nor would I be pleased if teenagers sprayed tags there. It's so subjective.