I just don’t see any pay off for launching a DDOS at any particularly pool. The only “useful” vector would be hitting the current leader to prevent minting a block, which would require some sophistication. Even then, I don’t know that it would even be useful in any real capacity.
I just don’t see the monetary reward for the attacker, so why would they waste resources on such an attack?
A sustained attack from a rival pool kinda makes sense if your goal was to force delegators to leave. It would have to last many epochs, so it’s highly cost prohibitive. Even if you could pull that off, delegators would migrate to many different other pools, so the payoff is zilch again.