What would we become in such a universe? We would take a step back, it will become about survival again (I know it's like that on earth here and there), not about growing together, exploring. It's like Star Trek's mirror universe.

Sure I'd fight for humanity, but I'd be so disappointed. Maybe even enough to just give up.

(I have to admit I just could not make it through part 2 of the Three Body problem, it went to slow for me.)