their reasons didn't seem very good.

Wired has unusually crappy commentators; YouTube quality. I wouldn't put much stock in their reactions.

I'm wondering whether the vaccine would mean that people would be more inclined to accept low status (it's less painful) or less inclined to accept low status (more energy, less pessimism.)

/blatant speculation

Stress response evolved for fight-or-flight - baboons and chimps fight nasty. Not for thinking or health. Reduce that, and like mindfulness meditation, one can think better and solve one's problems better.

is from objectively worse conditions

IIRC, the description made it sound like the study controlled for conditions - comparing clerical work with controlling bosses to clerical work sans controlling bosses.