There was a time when Gedolei Torah knew what they knew and knew what they didn’t know.
I happen to know Gedolei Torah and Roshei Yeshiva who use I-phones and the internet. Are they all doomed?
When it comes to Metzitza B’Peh, we are not discussing a Biblical Commandment, nor are we referring to a Rabbinical enactment from the Gemarah's time. We are referring to a hallowed Minhag from days of yore to use the mouth only.