Yes but if you only block the jugular's could you still like die from that? Would it take a longer time than 15-30 minutes? Compared to the Carotid arteries? Or no just the same amount of time, only you'll be in pain instead?
Yes, you would still die within about the same amount of timeframe (about 10-20 minutes, or 30 minutes with certainty). If blood can't get out of the head, it can't get in either, and the lack of fresh blood and oxygen causes brain death.
Forensic and medical examinations are always after the event, at which point it's hard to know how death exactly occurs when the carotids are not fully blocked, but there are a couple of theories. One is that after the person passes out, muscle tone is lost, and eventually the carotids do get blocked as well as the body goes limp, even if they weren't initially. Another theory is that as pressure builds up in the head, it causes tissues in the throat and the tongue to swell, which blocks the airway (note that the person is already unconscious at this point). Regardless of these additional mechanisms, the simplest explanation is the first one at the
beginning of my comment.
If your questions are just theoretical and you just want to make sure, that's fine. However, it isn't a good idea to do hanging if there isn't enough pressure. If someone wants to go for certainty and avoid complications, it's best to do it in a position that puts enough pressure on the neck.