Although LN has been advertised by some as a solution to lower fees, it was never that. LN is a scaling solution to allow you to send large numbers of transactions very quickly and without needing on-chain settlement (without needing to wait for confirmation).

Imagine a trader who wants to move their fund immediately to the exchange and sell it. Without LN they'll have to either keep their coins on exchange and risk losing all of it or make a deposit and wait for 1-6 confirmation that can take up to an hour before they can sell. With LN that's a matter of seconds.