I have a pretty good mental model of it in JS and TS, because it builds on the pre-existing Promises API, because the transpilation process let me see the equiv

I have a pretty good mental model of it in JS and TS, because it builds on the pre-existing Promises API, because the transpilation process let me see the equivalent vanilla code while I was learning it, and because the event loop plus the single threaded nature of JS meant that libraries were already using asynchronous code everywhere. When it comes to other implementations, though, I find them much harder to work with. In particular, existing synchronous or threaded code can block them, there's no good way to fix it without rewriting the synchronous code or shoving execution into a traditional thread, and all the existing libraries are synchronous. It feels like you need a completely new standard library to take advantage.