Correct, but thats the real reason for the back to office push. No one cares where you are, so long as someone has to pay for you to be there.

You put on your work clothes, which are basically the same as regular clothes but more expensive. You commute to work, you consume radio/podcast/whatever, you consume ads. You get into the lobby of your building and get a coffee from the stand that pays rent. You take the elevator to the rented offices you work at. You get exploited as much as is legally allowable for 4 hours. You go back downstairs and buy food from another rent payer. You go back upstairs and get exploited some more. You consume more advertising on the way home. You get home too tired and too late to disrupt anything that makes rich guys richer.

None of the real reasons are productivity related.