True, but there's an opportunity cost to having worked at Company X on the assumption that your RSUs would appreciate in value, when in fact they decreased and you could have worked at Company Y instead.
Anecdotally, I've never had RSUs depreciate to a point at which I metaphorically lose money for my efforts. This might happen at startups more often and megacorps less often.
We were in an unprecedented bull run for tech stocks for a decade plus. No guarantee that continues. Markets are anti-inductive and past performance is no guarantee of future results.