You must have skipped over one of my points, as I said that with a web / structure techs could have optionally needed techs. For example if there is a later tech that has a requirement of having one of 5 different techs, the player can take a different route through.
The replacement you described seems way too abstract to me to be doable. I think your example is fine with experimenting with materials for making tools or making something sharp enough to attack some other species. However when you get to the later techs, how would that work? Does everything have a “space worthiness” stat? I find that not really doable.
I fail to see how this applies to technology. More relevant discussions:
I don’t think this kind of split is really good for a “tech” tree. It’s not really possible to get to space without engineering, though politics and such can help with that. So instead I think there should be one huge tech web with only technologies. And then other things would have a different tree, kind of like in civ 6, but we could have even more different trees. The trees would also give bonuses to each other to encourage using them all.
Anyway, back to, the feasibility argument. I just don’t find any too dynamic system to be really possible.
I think the early techs, when the player maybe hasn’t unlocked the RTS view could be done, as you describe, through experimentation etc. But in RTS mode the player basically has thousands of scientist they command to “look into this tech that is starting to look possible now”