You're right on that level of communication, however there's more:
the nodes have sensors, so upon events (or timer) they send measurement data to the base. Depending on the type of sensor and the amount of events, you can get a whole lot of sensor messages (100s per sec), and when the ACKs are missing it retries even more (resulting in the base being flooded with copies of the same message).
And in that case, the entire network goes down (all nodes are impacted) and the base can even not request the sending node to stop sending. The only thing I can do is manually powering down that node, and then the network (slowly) recovers.
Of course, I can try to bypass the problem by limiting the amount of messages per sec a node can send, but that is only a patch and it does not solve the fundamental flaw of the network protocol. Moreover, when the amount of nodes increases, limiting might not be sufficient.
So the problem with one node retrying sending many messages and bringing the communications down remains.