IMO there's not much to see here.

Attack 1: If a set of zombie nodes stop operating in the lightning network, the network can be severed. If you coordinate it for maximum impact, the time it would take for all the affected parties to close their channels and open them with non-zombie nodes would be longer than the channel closing locktime because of chain congestion.

Attack 2: If you close a channel with an old state, the other party can submit a follow up transaction to take all of the funds in the channel. This doubles the amount of chain congestion you can cause. And if you can cause enough congestion, maybe you can close some channels with old states because the other party can't get their revocation tx added in time. Thus allowing you to double spend the coins.

Not too worried. The first attack boils down to throwing away a central position in the network and gaining nothing.

The second attack is like launching your money in the air and hoping in the commotion that you find a sat on the ground.