i'm pretty sure js transpilers are a symptom of having to support many js environments and js versions but folks wanting to have access to current language feat

i'm pretty sure js transpilers are a symptom of having to support many js environments and js versions but folks wanting to have access to current language features anyway. people have made this too for python and it's called `3to2`, which is a backwards version of the `2to3` language upgrade tool. babeljs for example used to be called `6to5` so i don't think it's lockin that causes this desire, but it's certainly true that the options for clientside programming languages that are widely deployed are fairly slim. i don't think they're related though.