I see what you're saying, but Bosch may not be the best example because frankly his paintings often look like the early AI fever dreams lol (I mean, not really, but you can see the resemblance). But seriously, with enough randomness you certainly could get that kind of output - there's really no reason why not - but it would take god knows how many iterations and the computer doesn't have everything other than the art to determine what is good.

It's monkeys and typewriters, yknow. You'll get there eventually even just producing random pixels (I mean, admittedly one limit will always be resolution unless you actually teach the AI to operate an arm which paints).