Spun off from 2020's viral
打工人 (dǎgōngrén, "worker person") meme, which recast the somewhat blue-collar term
打工 (to work for someone) as a self-deprecating label for white-collar cubicle slaves.
打工魂 pushes the same joke into mock-epic territory — burning the "worker's soul" for someone else's KPIs.