The ideas stupid people come up with are statistically more likely to be wrong, so if we rewarded them unconditionally for having original ideas, we'd end up incentivizing the production of wrong ideas. It may actually be a good thing that "having original ideas" is a specialization of labor largely restricted to the intellectual upper class.
I accept the premise that "the ideas stupid people come up with are statistically more likely to be wrong," but I would add two caveats. First, "within the domains in which those more intelligent people have relevant knowledge and draw on that knowledge," and second, "Even then, for any difficult problem the majority of original ideas will be wrong even from more intelligent people."
I would propose that the intelligent people might be more useful in sorting right ideas from wrong ones, than in trying to generate all the ideas themselves.
One of the big variations I see between people is the amount of energy they habitually put into thinking, and I haven't seen this discussed anywhere.
General advice about improving health and lowering intellectual friction would seem to help increase the ability to think, and ideas like "take five minutes to consider the problem" adds impetus, but I'm not sure what the general difference is between me and most people, or Yvain and me.
Intellectual drive isn't an unalloyed good-- cranks have high drive combined with low self-editinig, and some types of depression include a compulsion to think about topics that cause misery and/or inertia. Part (all?) of the value of meditation is getting some time off from thinking. Still, increasing intellectual drive would probably be a good thing for a lot of people.
Has anyone found that rationality training or anything else increases the default desire to think?