I've certainly seen code that made me cry. :)
I don't think computer art is a complicated problem.
Firstly "hand+brain+physical media" has infinitely more degrees of expressive freedom than "pixel robot."
Most pixel robots are really, really dumb.
At worst they draw simple filled shapes. At best they run some minimal - probably recursive, but still trivial - algo thing that makes nice pictures.
But art is not about making pretty pictures. It's about abstracting and intensifying human experience - which is a completely different problem.
Canvas and pigment can be a convenient way to do that, sometimes.
Code is never a convenient way to do it, because it's a very rigid and primitive medium explicitly designed to eliminate the subjectivity and intensity art specialises in.
So even the most interesting computer art is usually just shapes arranged in some semi-random way.
If it has texture at all - often it doesn't - there's absolutely nothing happening under the surface.
You can maybe say the same thing about some more abstract work.
But you certainly can't say it about art as a whole.