The internet backbone is composed of multiple, parallel 10gbs connections.
The routing engines all on ASICs optimized for forwarding speed.
To select for content in those massive flows is not feasible. Though they probably would if they could.
It’s the on ramps and off ramps where content selection occurs. And it does occur. Constantly. By any number of entities. None of them with your interests in mind.
Yes.
The inside of every closet that doesn’t exist is pretty much exactly like every other closet... except that it doesn’t exist... as far as you know... even when you’re in it.