Between half and a quarter of all the Waystones in the network have been destroyed. Given what the network needs to look like, that, to my mind, supports my understanding of the situation.
If you don't want to discuss it anymore fine, but with up to half of the Waystones missing, and presumably any Waystones upstream of those missing ones that survive being inactive, I think it's very plausible that a high proportion of the surviving Waystones in the Empire fall into that category, assuming the druids at least, were going around switching off Waystones to prevent cascade failure. Destroying even a quarter of the nodes in a network with multiple layers should leave loads of orphans cut off from the central nexuses.
It could easily be that only a small fraction of the original network being active is required to prevent the Empire going to Hell, but that's not enough to drain enough magic to prevent the mutation/corruption/etc that one that wasn't a shadow of itself would prevent. I'm not arguing that it isn't doing anything at all. Just that most of it isn't working.