This is another one of those things that I would argue is a continuum, not a binary dichotomy. I think it's totally reasonable to posit that human intelligence is not "fully general". But I would have a hard time with suggesting that we don't possess a certain measure of "generality" in our intelligence. I mean, humans have dealt with new situations before and apparently thrived despite that. Imagine the first human to live in an environment near an active volcano and who witnessed a volcanic eruption. Or just think in terms of new technological innovations - our intelligence is "general enough" to learn to use telephones, drive cars, do abstract math, etc. All things that the stereotypical "caveman proto-human" did not have to deal with and which would have been new to somebody at some point.

> On a Meta note, what if we don't have general intelligence.

This is in fact more than likely. Depending on how one defines “general inteligence”.

There are problems which require superhuman reactions. (Think of plotting course to intercept a missile barage with multiple interceptors.) There are problems where our brains can’t fit the variables required. (Imagine a 5 dimensional Rubik’s cube with a billion segments along each edge for example.) There are very specific circumstances under which our inteligence can even function. (Imagine as simple a challenge as tying your shoelaces while exposed to the vacuum of space, or a room temp atmosphere of pure chlorine gas, or enchased in molten metal.)

Heck these supposed general inteligences can’t even reason themselves out from their own climate change experiment, or prevent viruses from harming their bodies.

There's certainly no reason to suppose that natural selection could be capable of producing truly general intelligence. And I'm a fan of the theory that says our brains are too simple to be able to truly understand how our own brains work. And no matter how increasingly complex our brains became, that would probably always be true. But it is remarkable how much we do seem to be capable of - certainly far more than was ever necessary for us to compete against other species for survival.

That would not change the fact that humanity an be collectively weak (or individually costly) in solving known problems, hence a need for Intelligence development.

Isn’t that what complexity theory is about? …how similar classes of problems are to things we know how to do?