Regarding tax breaks, I never saw any, but that was pre-pandemic. That makes more sense to me, but leases requiring minimum attendance counts seems like it could be an oft-repeated myth.
The lease is locked in. From the company's perspective, the building is now free, except for marginal costs per employee that shows up. So the only remaining math for the company to consider is, are the benefits that the company gains from an onsite employee greater than the $2/day it costs to provide coffee and toilet paper? Remember, the company is happy to outsource the cost of commuting to employees, and only cares about the value of the building if they own it. And they have great institutional difficulty in weighing intangible employee satisfaction against other perceived gains for the company.
Under this logic, I think it's easy to see why management, acting in the company's best interest, is pushing RTO so hard. If it costs employees $10/day but makes the company $3, that's free money.
The mental gymnastics folks go through to support one side or the other in this debate is just mind boggling to me, especially since their are much simpler and more likely pros/cons for both WFH and RTO.