It's parroted because it's correct. It doesn't matter if companies own the building or not, because leases are often on 7 or 10 year terms--sometimes more. They're stuck paying that and associated baseline heating, electrical, etc. costs.

That's exactly how the Sunk Cost fallacy works. CEO's don't let it slip because nobody wants to admit they've fallen for a fallacy; that's assuming they recognize where they've gone wrong in the first place.

Conversely, look at what evidence they're providing that return to office mandates are better. Lots of vague statements about "ideas coming out of random encounters in the hallway" with no actual evidence to back it up. It's certainly none of the reasons they provide, so we should go looking for others. Sunk Cost of real estate fits their behavior pretty well.