It's hard to tell, but from what I've seen the people who have trouble setting boundaries when working from home are the same people who would consistently put in extra hours in the office, answer email at 11pm, etc.
I feel really irritated when I see them blaming a flexible work environment for the same problem they had before, and asking for the entire workforce to be subject to restrictive conditions so they can have an ineffective incentive to stand up for themselves.