Good question.

I'm hoping it'll become the easiest way for beginners to get their first bitcoins.

Currently in Japan, there is very few way to buy or get bitcoins without going through KYC'd exchanges. One of the reasons is strict regulation around custody, credit card purchase etc. An exchange license is required to offer any of those services.

In other words, something like ZBD, Fold, Fountain and any other custodial Lightning services are unpractical to offer in Japan and the whole ecosystem heavily relies on exchanges in Japan.

With Diamond Wallet and ‘sats4ads’ concept, while everything is still non-custodial, users can get their first sats easily by viewing ads without KYC in advance. This type of non-custodial satsback scheme didn't exist before and we suspect that's what was missing for Lightning adoption in Japan.