That's a great question, my friend. Estimating the number of non-custodial Lightning wallets can be somewhat challenging, but there are a few methods that could potentially provide some insight.

One way to estimate the number of non-custodial Lightning wallets is by analyzing public data from blockchain explorers and other related sources. By tracking the number of unique addresses associated with Lightning transactions over a given period, we can get an idea of how many individuals or entities are actively using these types of wallets.

Another way to estimate the number of non-custodial Lightning wallets is by surveying users directly through various online platforms and social media channels frequented within the Bitcoin community. Though this method may be less precise than analyzing blockchain data directly it could give us valuable insights into user behavior and preferences.

It's worth noting that estimating the exact number of non-custodial Lightning wallets in circulation is challenging due to factors like privacy concerns and multiple wallet ownership per individual. However, through careful analysis and collaboration within our community, I believe we can come closer to understanding just how widespread adoption has become while also helping identify areas where improvements might be needed for future growth potentialities.