Lightning Network is a BTC wrapped in a multisig. And yes, "wrapped" is the correct word for that, because if you "wrap" it in one channel, you cannot "wrap" it in another at the same time, and on-chain interaction is needed for each wrapping and unwrapping operation. Also note that in LN there are millisatoshis, so if you execute something on a single millisatoshi, then it would not exist outside of LN (so million users having 1 millisatoshi each will have zero BTC on-chain, there could be 1000000-of-1000000 multisig with 1000 sats, but it cannot be unwrapped and splitted between million UTXOs, because of standardness and dust limit).

Also note that each Taproot address is potentially wrapped N-of-N multisig. Because from the on-chain perspective, you can have 1000-of-1000 multisig, and it will be expressed as a single Schnorr signature. And then, you can have this N-of-N "everyone agrees" signature as a base for any Turing-complete contract you want.