Is there a name for this line of thought?
Often I'll get an idea, then I'll think about how simple it seems and how it's likely already been tried / done a million times, and I'll drop that line of thought. But then I think about how that exact thinking has probably kept countless others from attempting it. It's like a crowd effect, but across every developer through time.
This isn't very helpful, but yes there is a term for it - however I have forgotten what it is. It's something like "god complex" but not quite that. Sindre Sorhus actually told me once but I can't find the message off-hand.