I guess what I’m getting at is that most current browsers support very nice JavaScript features anyway. And instead of adding yet another layer between our code and the browser—embrace the current generation of (at this point very robust) language features available.
And if that’s not good enough use something like TypeScript!
Maybe that's true for users in the western world. However, if you are in the asian market, there are popular browsers you've nerver heard of (some localized fork of chromium that's way behind). That is not to mention the poorer populace of the world still uses whatever that runs on WinXP or something, if they have Internet at all.
As software engineers it's not our job to use technology to dictate (control) how people access information, telling them to use newer browsers and newer hardware and what not, our job is to support as many people out there as we can.
I mean, how does that not just push all of this towards companies and open source solutions that provide access to old browsers and what not? I mean no matter what direction you push, it's going to be someone else's open source code that needs money.