I would argue that the statement “Making a future full of flourishing people is not the best, most efficient way to fulfill strange alien purposes” is nearly tautological for sufficiently established contextual values of “strange alien purposes”. What is less clear is whether any of those alien purposes could still be compatible with human flourishing, despite not being maximally efficient. The book and supplementary material don’t argue that they are incompatible, but rather that human flourishing is a narrow, tricky target that we’re super unlikely to hit without much better understanding and control than our current trajectory.
I would argue that the statement “Making a future full of flourishing people is not the best, most efficient way to fulfill strange alien purposes” is nearly tautological for sufficiently established contextual values of “strange alien purposes”. What is less clear is whether any of those alien purposes could still be compatible with human flourishing, despite not being maximally efficient. The book and supplementary material don’t argue that they are incompatible, but rather that human flourishing is a narrow, tricky target that we’re super unlikely to hit without much better understanding and control than our current trajectory.