Yes, selective breeding is basically humans inducing evolutionary pressure by allowing or disallowing certain individuals to breed.

Domestication can occur naturally (as we believe happened with cats), and more generally there's no reason organisms can't develop traits that humans like except that there would need to be an existing evolutionary pressure to promote it. It's not so much that the traits are harmful as there's just no need for them (apart from everything we've bred to be sterile or completely dependant on humans)

Given enough time evolution turned water-breathing fish into giraffes; there's no reason bioluminescence would be impossible to select for, it would just take an incredibly long time.