“The R”Y’s who follow the mesoras have to be able to answer it though. So ask them.”
This makes it seem as though you have never asked them yourself. So how pray tell do you know that there are any Roshei Yeshiva who hold this way? And if you did ask them, we are all waiting with bated breath to hear their answer(s).
What I know is that they hold Mesora is a basis. I am personally not concerned with why that is so. There are plenty more necessary and important things to learn first. And it’s likely the answer is not pashut to understand, especially in a vacuum.