For me, going back to the office means going back to eating microwaved leftovers, or spending $15-20 a day on lunch out.

Totaling up gas and mileage and food and tolls, commuting to the office is going to cost me on the order of $500-1000 a month that I'm not spending now. Just the extra time that I'd need to spend getting ready to go to work and then commuting works out to an entire extra work week of time over the course of a month.

On the other hand, where I live the marginal cost of an extra bedroom (to put a home office in) for a city apartment is about $1000 a month. In some higher cost of living cities it will be more.

It’s be cheaper out in the suburbs, but even then it might be another few hundred a month.

I’m surprised that people are talking about things like electricity costs when real estate costs are so much higher.

Absolutely for employees, the biggest (I'd probably argue only real economic downside) is more space if the company is urban and they really want to stay urban. Arguments around electricity are ludicrous and food only applies to a very limited set of companies.