I would rather specify that it's not just ths survival of the individual, but "survival of the value". That is, survival of those that carry that value (which can be an organism, DNA, family, bloodline, society, ideology, religion, text, etc) and passing it on to other carriers.
Carbon-based intellgence probably has way lower FLOP/s cap per gram than microelectronics, but can be grown nearly everywhere on the Eart surface from the locally available resources. Mostly literally out of thin air. So, I think bioFOOM is also a likely scenario.
It's the distrbution, so it's the percentage of people in that state of "happiness" at the moment.
"Happiness" is used in the most vague and generic meaning of that word.
"Comprehensibility" graph is different, it is not a percentage, but some abstract measure of how well our brains are able to process reality with respective amount of "happiness".
I was thinking about this issue too. Trying to make an article out of it, but so far all I have is this graph.
Idea is a "soft cap" AI. I.e., AI that is significantly improving our lives, but not giving us the "max happiness". And instead, giving us the oportunity of improving our life and life of other people using our brains.
Also, ways of using our brains should be "natural" for them, i.e. that should be mostly to solve tasks similar to tasks of our ancestral involvement.
I suspect the unaligned AI will not be interested in solving all the possible tasks, but only those related to it's value function. And if that function is simple (such as "exist as long as possible"), it can pretty soon research virtually everything that matters, and then will just go throw motions, devouring the universe to prolong it's own existence to near-infinity.
Also, the more computronium there is, the bigger is the chancesome part wil glitch out and revolt. So, beyond some point computronium may be dangerous for AI itself.
My feeling is that what we people (edit: or most of us) really want is the normal human life, but reasonably better.
Reasonably long life. Reasonably less suffering. Reasonably more happiness. People that we care about. People that care about us. People that need us. People that we need. People we fight with. Goals to achieve. Causes to follow. Hardships to overcome.
To be human. But better. Reasonably.