I couldn't agree more. As the co-founder of an app development company curently working on our flagship I have had a very similar experience. Although I wouldn't call myself an expert in the field it will impact (and I think some app/product/innovation ideas are going to potentially affect a field that you couldn't be an expert in without dedicating your life to it) I was surrounded by people involved in the field. I think the most important part of your article for me is being open to the idea that, with the current tools, a problem might not be fully solvable. Setting out to create something to fill a gap will just result in you imagining that a gap exists where it doesn't. Good product ideas come from the organic realisation that there is something missing from the market, and the best way to do that is to be open to the idea that apparent limitations could be the bounding box of what defines your product/app.
Yes, and although I won't say to always trust that "feeling you get".. there is a feeling that you get when you organically come to that realization and it's very different from sitting in a brainstorming session and thinking of 20 ideas in a row. Can't replace first-hand experience in a space.