Yes, this is confusing. I have chosen dedicated workspace as an amenity for my listings because every bedroom has a desk and chair for guests to work from. That was the definition given by Airbnb, i.e. a workspace in a room where the door can be closed, i.e. not a shared/public space.
They are now marketing it as a separate room just for working, i.e. a home (or other) office, which is totally misleading. Plus, my WiFi is good and most guests are perfectly happy with it, but it's not the equivalent of a corporate office building's WiFi set up.
It's only going to lead to guest disappointment and bad reviews.