Do not mistake what I said for some claim that all art is bad/ugly. There is a lot of art I do enjoy. What I enjoy is personal. I do not fault someone else for enjoying art that I don't enjoy in general.
I find Da Vinci the engineer makes things I find nice to look at, but he did many other paintings and I would need to see each to make a judgement on it. Knowinghis issues just makes me wish he lived with modern medicine where we might be able to treat him - and wonder what he could have done if he had modern training - many of his machines have obvious flaws that his day was not advanced enough to know about. That is me though, maybe you are different - this is a personal thing and so it is hard to call anyone wrong.