This is a silly thing to jump towards in the discussion, since it's not like we are anywhere close to the situation in which we have next to no private transport. In fact, we are almost at the other extreme.

But if I was to indulge you, I would say that public transport doesn't mean rails. In the case of buses it also uses roads. And of course, if we were to abolish all motorized private person transport (again, no where even close to that) of course there would need to be a system to allow for the transport of items that are too big to be transported by individuals in public transport. I assumed that goes without saying.