I honestly see no difference whatsoever between the "Ordinals Attack" and the Lightning Network Attack on Bitcoin. They are literally the same thing.
I honestly don't see how you can even begin to compare the two.
In Ordinals Attack you are storing arbitrary data (like bytes representation of an image) in the bitcoin blockchain by exploiting a flaw in the Taproot protocol. That is to treat blockchain as a cloud storage.
In Lightning Network the only thing you do on-chain is to send bitcoin in normal bitcoin transactions to a normal bitcoin address whenever you open/close a channel. There is no extra junk data being stored on chain. That is to treat blockchain as a payment system (what every other tx is doing too).