@zipperback
Interesting, I've not really thought about it (nor have I met with this opinion much) I'll lok at this topic, sounds interesting. That said, wouldn't the Mongol Empire also be a significant factor in the facilitation of the trade between the East and the West, and the spread of technologies associated with it? Probably a bigger one than the crusades ,really, since the scholarly consensus currently seems to be that it was them who brought gunpowder to Europeans? Also, a lot of the knowledge which was "rediscovered" during the Renaissance seems to have been already known to the Byzantines. It would have spread to the West sooner or later tbh.
I don't mean to dismiss your argument, clearly you've done some research into this, but I honestly can't say I share your idea of the Crusades being so paramount in this. There were a lot of factors at play, and looking at the larger picture, the spread of this knowledge and technology into Europe was unavoidable. Too much trade and contact was happening for it not to happen, sooner or later.
Also, to make my original argument more clear, while Europeans gained a lot thanks to colonization, the only reason they were capable of doing it in the first place was thanks to already enjoying massive advantages over the peoples they were attacking. Even at the start of the invasions of the Americas, they were already matched only by the other highly developed (for that time) Eurasian civilizations, while their opponents were, well, not, to say it mildly.
And then, after 1760s, came the industrial revolution, Europeans leapfrogged over the Asian civilizations who roughly matched them up to that point, and gave them the same treatment they were giving other less advanced civilizations for a couple centuries by that time.