I think the best way to make Nostr mainstream would be marketing it as a platform where you, the users, can make money.
If only such a thing truly existed. 😂 But unfortunately: "Your Alby Hub is currently offline"
Discussion
Make the tools as turn key as the systems they currently use and then hit them with the they get to keep all their revenue
Maybe spark.info solve these lightning problems.
That's why I think an advertising rewards relay (similar to brave rewards) could be an avenue to attract some people
(Just as one, small aspect of 'making money', obviously.)
NIP-60 adoption fixes this, your npub comes with an e-cash wallet that can send and receive zaps.
We're 10 years early to the party.