20 points on average might push enough people from "unable to genuinely perceive long-term threats as threats" to "able to genuinely perceive long-term threats as threats", that it would move us past the political tipping point of collectively caring enough about doing something meaningful to both figure out what to do (devote money and resources to research) and to do it.
Individual carbon footprints are not meaningful - it doesn't matter how well an individual paddles their canoe when that canoe is in a swimming pool on a cruise liner. What matters is how the liner is piloted. If all people suddenly disappeared off the earth, except for those people who happened to be standing in Walmarts at the time, do you think that society would be better or worse at recognizing and handling abstract, long-term threats like global warming than the society composed only of graduate students would be?
you mean the thing that allows any of those other things you listed matter at all?
and with all those abilities, it may make no difference, so there's no evidence that the difference in intelligence between yeast and humans is sufficient to save us. then why would 20 more points do it? and if yeast survive but people don't, what then? the point is in both the case of the yeast in the bottle and the human case our drive for survival kills us when we move into sudden abundance. greater average intelligence would just bring that abundance on faster.
since we can't seem to steer this ship, we're at the mercy of the currents. despite all our metaphors and plans and concern about global climate change we don't seem able to do anything. is there much of a difference in carbon footprint between your average walmart shopper and your average graduate student, concern notwithstanding?