Plus Lightning has increased Bitcoin's utility by a thousand times by making it possible to transact to the "millisatoshi" level, a thousandth of a satoshi, and without changing the basic parameters of the Bitcoin network.
franky1 believes it's an "abomination" though. Haha.
Any positive feature, try to spin it as a negative. That appears to be the game.

Still, the best argument remains that no one can prevent people from building this network. And no one can force others to build every single feature into the base protocol. Some things are naturally going to be built on top, because it's all permissionless. As to Lightning's success and longevity (or any other feature built as an additional layer, for that matter), that's entirely up to users. If it provides them benefit, they'll use it. If it doesn't, they won't. So why not just see how it plays out? Arguing from a theoretical standpoint can only get us so far. Sometimes you just have to go ahead and do something to find out for sure.
It's also funny that those are the same people that say the Core developers suppress Bitcoin's growth because of their conservatism in development.
They have their big blocks, they can experiment, and break their network if they want. Which is also good in my opinion, because it would show everyone what not to do. If it's a success, then it's a success.