Coobinators were probably idiots anyways.
[snip]
Now you have me thinking about this.
They make sense if older MGs become steadily more emotionally stable, generating less and less energy (As they shift from young girls to immortal warriors), that they have humanity seeded across many planets, and that they prefer to destroy civilizations before unpredictable people with alien ways of thinking develop to the space empire stage and have any ability to threaten them.
They might not even want lots of excess energy. Perhaps politics (internal or with other civilizations) gets in the way of gathering 1000x more than they need to stave off entropy.
The latter half of the first bit is something I've considered, but the first bit I'd disagree with. Literary cliché aside, there's no reason for someone who's 2500 years old to be any less emotional than someone who is 25--and that's assuming that MGs' bodies actually age at all. If they
don't, then they're still dealing with puberty-levels of hormone-driven emotional peaks even without interference/enhancement on the part of the coobies. Granted, wisdom can temper passion to some degree, but humans are fundamentally emotion-driven creatures and what we can observe among the very old doesn't really support the idea that age and experience will dull emotions.
As for the other, it
is a valid concern for them to have... but if they're legitimately and provably benevolent and helped bootstrap humanity without attempting to exert any sort of imperial control, it seems more likely that jolly cooperation would persist. Better yet, as humanity (and whatever other species they've approached) develop and mature, the primary Incubator concern becomes the primary
human concern as well-if there's something having a population of immortals
would do, it's removing the lifespan-limited blinkers that have generally prevented us from exercising good long-term planning.
The last is probably the best explanation for why they don't ramp it up, but it doesn't explain why they don't use a more efficient and less evil method on a small scale.