It also isn't entirely true the entire network is/was at risk. Not all nodes connect to all other nodes. So a malicious actor would have to waste the money and only bring down the nodes directly connected. Most nodes today aren't accepting new connections. Also it only affects full nodes not SPV. I think the best attack vector would be to crash competing nodes but remember they have to spend a block reward to do so and all they get in reward is a block reward. The miners have enlightened self interest to not do so. I think the risk has been blown out of proportion but they are being smart and showing an abundance of caution to make sure this does allow for use case they aren't considering or some other cascading failure.
You can walk the network and crash all nodes with listening sockets, this ruins pretty much everything. There's some non-public infrastructure that would perhaps make mining continue, but non-listening nodes can't exist without sockets, and neither can SPV nodes.