It is an off handed snark based on the not terribly subtle difference between "not a professional" and "unprofessional" which I feel perfectly validated making

It is an off handed snark based on the not terribly subtle difference between "not a professional" and "unprofessional" which I feel perfectly validated making because Sway isn't a volunteer effort, it is an (un|insufficiently) paid effort, which is also not a very subtle difference.