My progress in the Brotherhood of Steel questline has been completely stalled, I'm not sure if it's related to the quest or not since I haven't been to the settlement there in a while but I tried to fast travel to Greentop Nursery to reach the next checkpoint (Listening Post Bravo), I noticed that the Settlement says it has 20 people at it which was a surprise since last I checked it had maybe 10 and my charisma is only 6 so I don't think I should even be able to have 20 people but the problem started when I tried to fast travel, I was in the loading screen and the game crashed to the desktop, no error messages or anything.
I figured I'd try to trek over land but whenever I get too close to the settlement it still crashes. I tried going from the other direction to reach the Listening Post but about 10 m from the door my game crashes to desktop again so I guess it's just too close to whatever's causing the crash.

EDIT:
Fixed somehow, either it was just a temporary issue or else conquering another settlement helped, hope this helps anyone else who encounters the issue.

Nope, now it's back again, crashed again when I tried to fast travel back to the Prydwen and the save reverted to one before I finished the quest and it is now crashing when I go to Greentop again. Will try to replicate fix.