Echo JS 0.11.0

Is your site mostly static content with a few one-off bits here and there, it may be more useful than setting up a full-on bundle/build process.

Is your site a green field project where you're going to use modern frameworks or libraries where a bundler is easier to integrate?  In that case, using jQuery is probably a waste over piecemeal options and micro libraries.

It depends on what you are doing:

If you are coding some app type of thing, you probably won't need it anymore.

If you are building a typical wordpress website, with sliders, lightboxes and a bit of form validation then it's still handy to throw jQuery plus some plugins at the problem.

No.

It might not be relevant for your work but for those who still have to support old(er) clients like IE7/8/9 and/or old versions of Firefox, Safari and so on.