It has nothing to do with profits. It's more profitable to have everyone work from home. Upper managers and executives simply prefer having everyone in the office because they like it. It's their preference.
Whilst it wouldn't surprise me at all if this was the case, I've seen similar things at other companies, it's a completely brain-dead strategy. The people who leave are the most qualified and capable employees who can easily find a job elsewhere and you're just left with all the people who the company swept up in the boom period where they were hiring anyone with a pulse.