it's not possible for every current and future monero user to cease using monero and take up a convoluted lightning setup. there's not enough room on L1 for them to all perform the necessary channel maintenance steps. there would have to be a blocksize increase, because lightning doesn't scale users. everything that was done to get around this problem results in total loss of sovereignty as well as increasing levels of information leakage.
this is just one of the many reasons why the mass conversion scenario envisioned by super testnet is not actually possible with lightning.