Good question! The impact of LN for payments in general is under appreciated. LN allows for any exchange to be done more efficiently and independently (i.e. without gate keepers), which opens up global commerce in a new way.
One area that we've been excited to see develop is the efficient monetization of machine to machine communication (e.g. APIs), perhaps via Lightning Labs LSAT protocol.
In 2020 or earlier, VC Angela Strange (a16z main fund) noted the trend towards "Every company becoming a fintech company". That's a trend that can be significantly accelerated by Lightning Network. Her premise is an acknowledge of how ubiquitous payments/payments tech are in the everyday lives of people in developed markets- in other words, people with access to a debit or credit card.
But better than access that is access to a Lightning wallet.
App developers generally rely on > third parties for payment processing and through them the > traditional payment rails that those payment processors depend on. That defines what type of payments can be done, when, with whom, etc. LN opens up the field by reducing the friction of the traditional payment rails. One of the simplest demonstrations of that is the new viability of micropayments. This is relevant to various forms of content consumption (gaming, blogs, pods, voice and video, etc.), machine to machine value exchange, and so on.
What are some of the most underrated L2 applications?