The way I see it once you’ve thinned the polyfills to next to nothing, the enduring feature of jQuery is the automatic list comprehensions. The ability to unselect all of the buttons in a form in a single call is still hard to match elsewhere. That and parent queries.

The main problem I have with the implementation is that it chooses to fail silently when the list is empty. I’ve fixed too many bugs of this sort, often caused by someone refactoring a DOM tree to do some fancy layout trick after the fact. If I were implementing jquery again today, I’d make it error on empty set by default and add a call chain or flag to fail silently when you really don’t care. I’ve spent a few hours poking around at jQuery seeing what it would take to pull out sizzle and do this, but never took things any farther than that.

At the end of the day jquery is about the old debate of libraries versus frameworks. We’ve been doing SPAs with giant frameworks long enough now for the Trough of Disillusionment to be just around the corner again.