Well, after watching the gameplay footage, I think we found the culprit behind why Silent Hills was canceled. Resident Evil 7 is a VR game - shot in the same manner as PT. With Del Toro's comments about the "new technology" they were planning on using for Silent Hills, I think it's safe to surmise that Silent Hills was also initially planned to be a VR game. But with Resident Evil being an overall more popular and profitable game, they cancelled Silent Hills in favor of Resident Evil 7 to be their flagship horror VR title.
Resident Evil and Silent Hill are made by two completely different developers.
Silent Hill is by Konami.
Resident Evil is by Capcom.
So Konami's decisions would not have any influence on Capcom. Other than that P.T. was definitely an inspiration for Capcom.