Some low-hanging fruit for sure, but getting there. If Phoenix supported LN addresses and was custodial for small amounts, it would be perfect.

IMO the main hurdle is simply demand. BTC is still establishing itself as a SoV / MoE, and normies don't care about transacting in BTC. They'd sooner use ETH + L2s + Tron to settle value in USD stablecoins. Kinda silly, but hey I don't make the rules.

Stablecoins will eventually fall off, as the USD is on a timer. That's when Lightning reaches mainstream adoption.