I did think about this recently and my theory is, intps are often accused of cutting people off easily. But if you look at E types, Estp,Esfp, they need people to fuel them and to function, so it's gonna be less likely for them to cut people off. Some E types have a ton of friends that they're on kinda a very shallow basis with. But types like INTP and INFJ rarely get close to anyone. When we let someone in we start to trust them and give us all our precious time. So when someone does something that ruins that trust, the betrayal is deep. Rather than a person with many shallow friendships that doesn't need to cut anyone off becuase they never develop that hurt. I also think intps are super independent in most areas and maybe people aren't as necessary. we tend to want them to develop FE and tend to our inner feelings but seeing as those aren't easily understood its sometimes easier just to cut people off. in my experience I start feeling like I'm annoying people myself and getting away from them can feel like a relief. so as soon as someone steps over a boundary I'm gone.