With infinite planes and infinite universes contained within infinite dimensions, every possible outcome has been acheived. So in theory, an infinite number of pylons work without any disruption, while an infinite number have been sucsessfully stopped. Planeswalking is still possible, so we can only assume that a pylon would only severe a plane from every single other one, not completly eradicate all planes, which in short would have destroied everything in it's entirety. Your conclusion is unfounded. You are attempting to associate the Butterfly Effect with a plane being severed, stateing that similarly resonante planes would be severed too. While this may be possible depending on the efficiency of the pylon, you are only blocking travel from your plane to all other planes and vice versa, as shown by the fact that planes walking is still possible.