y'all most not have heard of https://strike.me/ which operates on the lightning network to send whatever local currencies through btc instantly for little / no fee
If you run your own lightning node, lightning is non-custodial. But strike is just a wallet that uses their own lightning node. So, if using strike, strike has custody of your funds.
>If you run your own lightning node, lightning is non-custodial. But strike is just a wallet that uses their own lightning node.
I don't know the implementation details of the strike app, but I don't see why you can't keep the signing keys on the device itself (as opposed to the server), and the server is only used for communication with the bitcoin network. That way you don't need to run a lighting node, but they don't control your funds either. Thin wallets use this model I believe.
You seem to be correct, based on their suggestion that you download another lightning wallet[1]. My prior impression was that strike contained a lightning wallet and a custodial wallet (for their fiat exchange). That said, with low cost and instant lightning network transactions you can basically use it in a non custodial way (ie. transfer out the moment you exchange for fiat).
Regardless of your opinion of BTC or of crypto in general, 10 minutes to confirm significant monetary transactions that all parties can agree on, without the need for a central trusted authority, anywhere in the world, at any time of day, is a pretty significant achievement.
Edit: Lightning networks are bandaids on a prototype cryptocurrency.