That doesn’t make sense to me because it seems custodial lightning was preferred by plebs even *before* nostr existed and even *now* when there is no need for offline receipt. Like in El Salvador or Costa Rica, for everyday retail payments. Last I saw, WOS and Bitcoin Beach / Blink, were preferred before nostr, and probably still are. For your argument to be correct, I would expect to see widespread and growing self-custodial lightning usage in those communities. 

Am I wrong about that?

You might be right that the early nostr adopters were all using self-custodial lightning, but surely you’d agree that is not a representative sample of plebs. As nostr grew, it was probably destined to become mostly custodial because of the existing preference of plebs.  

I don’t know what percentage of lightning usage is custodial but I’ll bet that by almost any metric it will be custodial by a large and growing margin. 

Maybe this is unpopular, but my current thesis is that self-custodial lightning will become used only by federations, exchanges, and other custodians. We, the plebs, will all migrate to ecash, presumably to large geo-federations when they exist. I’m just guessing here, but that’s the trend I see right now.