People are quitting now because it’s socially acceptable now to do so. They were always ready to quit because they don’t like being treated like a thing (and not a person) by soulless businesses.
The cheapness and greed of employers is a true problem but also a symptom of this larger issue.
Trying to be nice to employees to get them back ignored the fact that everyone knows—businessmen would run over their employees with a steamroller if it would add a dime to the quarterly dividend.