> Regarding transpilation surely it's not as standard as you make it out to be? It's popular to be sure but handwritten javascript is not that rare nowadays, is it?
If you are building a modern web "app", not a one off set of web pages, then yes, it is the standard. It would be very weird to not see a compile (transpilation) step.
It's becoming less and less necessary. If you don't care about browsers with tiny usage you can ship ES6 as-is these days. All the main browsers support ES6 modules. And HTTP2 means having all those modules in different files doesn't have the huge performance impact it once did. About the only thing left (that isn't easily solvable) is stripping comments and minifying.
I'm just making a handwritten microproject. It's to be included in a very old gigantic internal platform so I didn't want to add any more build steps to it.
Everything was going smoothly, until someone said... It's not working in IE11 and some clients are still using it.
We ended up converting the js to an older version in a half automated/half manual way with babel... I'm so used to use some of the new features I didn't even remembered they didn't existed before.
I used babel before, but only now I realised really out how much pain it saved me over the years.