What on earth are you talking about. Why would anyone want to inefficiency simulate stackfull co-routines using system threads? And what does underlying engine

What on earth are you talking about. Why would anyone want to inefficiency simulate stackfull co-routines using system threads? And what does underlying engine design have to do with the JavaScript spec? Additionally why do you think anyone is advocating for the use of a single system thread per co-routine in a discussion about Java virtual threads, a technology does the literal opposite? There’s nothing preventing anyone from creating a JavaScript engine that simulates async JavaScript using stackful cooperative co-routines, all operating in a single shared system thread. Perfectly upholding the existing JS thread model, but substantially reducing the bookkeeping needed to produce useful stack traces.