IF both parties were actually better off, people wouldn't leave and stay gone. They might strike out, thinking the grass was greener, but they'd be back in short order.
That they're leaving and staying gone shows that the reality wasn't living up to the theory.
Employees are exhausted and their employers were only one part of the equation.
COVID and other personal issues are the others.
Thanks to healthy savings accounts, many people could afford to quit their jobs. Quitting wasn't 100% the employer's fault.
They've clearly concluded they're better off now than before, across whatever factors matter to them, so again, the reality wasn't living up to the theory.
It's currently cobfirming that the pre-covid reality of work wasn't living up to the balance in the theory where everybody ends up better off.
That changes nothing about my point though--if your employer was getting exactly the value they were paying you, they would be indifferent to keeping you employed. And vice-versa.