Whirlpool is obfuscation, nothing is hidden. All amounts and connections are visible. Need to run your own dojo or you give away your xpubs. Weak to Sybil attacks. Requires centralized coordinator. Expensive, slow, and tedious.

Lightning we can already rule out the way 95% of users use it with custodial or LSP wallets that have full insight. For the few sovereign users left: receiver privacy sucks, amounts can be probed, IP exposed by default, onchain footprint data leaks. And unless you're only going to send and receive from the other 5 unannounced nodes that exist, you route thru centralized nodes that reduce any help from onion routing.

Liquid is traceable. Only hides amounts. Custodial.