The way I see it, Lightning as a network is agnostic to stable coins. In Taro for example, only the edges need to support it. So, it's not really a Lightning feature, it's a way to use Lightning to transfer fungible tokens. It's still btc from a Lightning standpoint. The only question Lightning wise is if it's ready to handle the stable coins traffic. Meaning, it will require a lot more liquidity to handle the traffic generated by stable coins transfers and w/o better liquidity management tools in place, I think we should wait.