The only downside is that it defaults to custodial, but for small amounts I'd say that tradeoff is okay.

Imho all those little bots and wallets should have an automatic "sweep above X" feature that will periodically send excess sats to a self-sovereign lightning wallet.

More than 21k sats in wallet? Sweep to s@ts.dergigi.com and leave 6.15k sats in there.

Programmable money!