Compared to AoW3, where the emphasis was squarely on classes and thus said classes needed to be very distinct, I understand where you are coming from.
Also, this being a fixed tech tree, and being presented as a solid wall of tech, makes some of the things a bit hard to parse imho.
AoW3 had an actual book, so you saw at most 12 techs at any one time (unless you turned the page) and each one had a nice icon.
So I do get what you are saying.
However, I think the shift onto racial tech is a good one, and the tech tree works.
My only real gripe is it would have been nice to have something better looking!