Maybe a better example would be health insurance. Health insurance won't directly change productivity, but good luck recruiting skilled people if you dont offer it. Same with WFH in my opinion. A company that offers WFH isnt going to magically become more productive, but it will help to attract top tier talent. I know a lot of people that factor that heavily into their decision making over gimmicks like ping pong tables and free lunches.

I dont see working from home as being a paradigm shifting productivity enhancement but I do see it as something that has been shown to be workable, and companies that refuse to offer it will be at a disadvantage attracting skilled employees that can get that benefit elsewhere.