I believe there are two different ways people think about this:
1) Some see "reason", "intelligence", "free will" and/or "consciousness" as emergent phenomena that arises naturally from normal physical processes (or they dismiss the concepts completely as illusions for the same reasons).
2) Other seem to consider these somehow independent from physics, or if not will tend to hypothesize that it is linked through quantum mechanics to something more fundamental.
If interpretation 1) is correct, then we will probably see full AGI in our lifetime. If 2) is correct, it could be that we can never create "real" AGI, or at least not without quantum computers.
I've never seen anyone in camp 2 come up with convincing definitions of the terms, though, beyond "I know it when I feel it".
Anyway, it's really hard to have a discussion with someone with the opposite conviction, since these beliefs tend to be held axiomatically and/or religiously.