Thinking about thought

Most of my own research on subjects of interest relies heavily on the "originals", to see not only the insights we still reserve today for misquoting and attribution debates about what some particular great mind would have thought of something or other, but also what other baggage might have been wrapped up with it, what was broken about it. What often occurs from this account is whether obvious solutions to these fundamental problems are presented in the intervening years (for example, genetics and molecular biology Darwin's case for evolution, neither fields of research which even existed at the time) or whether obvious solutions from the past are now ignored, which lends me to ask why these weren't available to them, or why they're inaccessible to us now. What is it that we overlook? Was it really that hard to see? Why, what were the incentives? What changed? These seem like valuable questions for understanding the weaknesses and strengths of human beings and their institutions and communities in approaching and solving our problems.

I don't understand either why this should be considered a dismissive enterprise as a result. 

It sounds essentially like a rejection of the field of history as a viable project beyond its factual accumulations. Maybe that's the natural and inevitable result of teaching history in the manner of its factual accumulations rather than as a method of perspective taking as is its more fundamental philosophical nature, and the natural result of teaching science in a similar fashion with its fundamental basis as a method of skeptical inquiry also mostly neglected, if not rejected.