You can never be sure, especially if you're a newcomer to the field, that someone hasn't plowed that field before.
So what should a newcomer to a creative field do to avoid being blindsided and bankrupted by incumbent owners of exclusive rights? If there are no good steps that a newcomer can take, then this impossibility has a chilling effect on people even trying to become a newcomer to a creative field.
How many times have you heard someone who isn't in tech come up to you and say "I've got this great idea ..." and they haven't even bothered to do the most cursory search, which would have revealed that it's not original at all?
What kind of search?
Obviously you can't do this [an alternate-point-of-view adaptation of a culturally significant work]
This is a form of creativity of which society currently disapproves through its elected representatives. How does it benefit society for society to disapprove of this?
you pays your money (or in this case, sweat equity) and you takes your chances.
Why the subject-verb disagreement? Are you quoting (or paraphrasing) a work of which I am not aware? Even so, I don't understand how to ensure that I avoid attorney's fees, statutory damages, and other ways of losing even more than the sweat equity that I had invested.
Harrison admits to having thought "Why didn't I realise?" when others started pointing out the similarity between the two songs
So what should Harrison have done instead to ensure that he realized his having accidentally made such a blatant ripoff before publishing it and thereby opening himself to infringement lawsuits?