basically because they picked a fight and lost
no actual remorse
no actual remorse
Did they lose?
Pretty sure the prevailing sentiment among the C-level has effectively become "Get back to your cube and shut up because we said so, or little Timmy won't be getting his braces." here in the US.
Employers like control. Relationships (your example) are pretty similar actually.
Why would someone settle for a partner below their standards? Simple, they enjoy having control in the relationship. Why would an employer settle for a sub-optimal employee? Dependability and reliance.
C-Suites knew attrition would be high, and regardless of what the managers who had to implement the policy might have thought companies knew that return to office was just layoffs in disguise.