The person I replied to compared the stdlib to that of PHP and Python, both of which are backend components. Frontend land is getting frequent updates already, with a relatively good process, vendor backing and incubation in browsers, not sure what the complaint is supposed to be there? That it's too slow? Imho that's a good thing when it comes to most language changes.
Yeah is too slow, but is not only that, is that it makes senses for it to exist years on user-land as a library (or multiple ones) before being implemented on any standard.
For what it's worth, I don't think that's a bad thing. Assuming you're talking about jQuery and the like, what was adopted to the specifications is the consensus of many years and wouldn't have been predictable in the first few of that library's history. I mean, frontend land is incredibly fragmented and browsers are no operating systems. Clean APIs and stability, to me, are worth far more than being quick to adopt the latest trend. Otherwise we get competing pet standards again, "made for firefox / chrome" buttons, without significant developer adoption. Libraries and shimming aren't inherently bad, single line libraries on NPM are.