Companies rarely openly say decreased productivity is the reason of RTO. It's always obscured in positive-sounding rhetoric about fostering collaboration, etc. The real reason, whether it is actually became they are not meeting expectations on one extreme, or to stroke the ego of executives on the other extreme, or simply to justify office real estate, is known only to management.
By the same rationale, would you agree that if a company insists on workers returning to the office, the are clearly not meeting whomever's opinion?