Good point re: AWS and Google Tesseract being OCR that can kinda sorta maybe do semi-structured things. Since you are very well-versed on this topic, would you mind answering a few questions?
I agree that having the business outcome you want to achieve first will inform the best route, but generally speaking it is my pov that IDP as a software "category", let's call it, is still immature and illegitimate. In that there is no true market leader or winner who has capabilities and features/functions that cannot be beat or repeated. I don't know that to be sure though, what are your thoughts in your experience? Who have you used (assuming you are an operator/user and not just a category buyer)? To what ends?
I know people at a few of these firms, but as you can see, it's insanely crowded from legacy tools to consulting firms who have a software offering to start-ups focusing on it. And this doesn't even include the software firms that are very narrowly focusing IDP on a very specific business unit, like AP/AR only a la a fintech, etc.