I could argue that there’s no reason for any proof of work other than sha256 as these side chains should be merge mining, but we’re way off in a tangent thread.
The point is that smart contracts actually do something other than “authorize payment”, and fancy Schnorr signing modes don’t come close to replicating those capabilities.
And so long as there is a need for a programmable verification architecture, Forth-like languages are prttty ideal.