*if* they manage to largely supplant existing tether usage (not sure why they would unless the fees are a ton lower, so maybe, unlikely?) then maybe it drives enough merchants that support receiving payments over LN invoices that it drives the ability to pay with lightning broadly, but that seems quite a ways off and SOL is ETH L2s are way ahead.
First they need someone to build a good consumer wallet, which is at least a few years of work.