So why not just tell people about how to self-custody their sats on-chain to start, and only keep a small amount on custodial wallets?

If I’m at a bar and I want to pay the bartender in sats, I will say to them: Just download this app, and in two minutes, you will have a wallet​ set up where you can receive bitcoin.

I am not going to tell them to buy $500 worth of hardware, wait days for it to arrive, watch some YouTube videos to learn how to build a node, install and configure a bunch of open source software, wait a week or more to sync the entire blockchain, buy $1000 worth of bitcoin and deposit it on their core wallet, then join a bunch of Telegram groups to find random strangers to open channels with, then download an app on their phone to connect to their node, then sign up for another service to give them a Lightning Address just so I can send them 5000 sats.