Lots of good choices outside of rails. There are some nice things about rails but speed and how it handles assets (asset pipeline) can make for some annoyances. If I want an app that will need to scale to higher volume in the future rails might not be my first choice.

jquery 2.0 has removed all that cruft to deal with IE.

Agreed.

Whenever something gains great growth there comes a point where people will decry it simply because they want to use the next new thing. Jquery is still widely used. Its a tool. Javascript has evolved and there are many things that can be done easier than in the past, but there are still times where you can do it with less code in jquery. Every new library or javascript framework goes through this cycle. Right now as popular as Angular has become people are already complaining about its shortcomings or how it clutters and breaks conventions. You also see this with CSS as things like flexbox make people question whether you need a responsive css framework like Bootstrap or Foundation. This is the up and down sometimes manic depressive nature of web development. Another factor influencing this trend away from libraries is what I call "the smartphone effect". Smartphone's made the push for minimizing page size as big a deal as it was back when people used modems and isdn. There was a time right before smartphones when bandwidth and browsers were really picking up steam. Suddenly loading larger pages with more features and bytes wasn't that big a deal. We didn't have to worry so much about slower internet connections and bad browsers (well except for all the IE variants). Unfortunately once smartphones grew in popularity that problem cropped up again. Suddenly the world of web development had to take a step backwards because browsers on smartphones were not as robust and we had to deal with slower cellular connections. Keeping your page size to a minimum was always important, but it became more critical again with smartphones. This is one of the reasons there is a push to use native javascript, native css etc because it keeps things lightweight and contributes to a faster loading page. With that said, smartphones and tablets have really improved a lot over the last few years. They are faster, the browsers are improving and connections are getting faster. Its always good to know how to work with raw js without a library. If all you know is jquery that's not good. There are many times where you may only need raw javascript even though you may be using jquery. Also be aware that you don't need to load the full jquery library. These days its easy to create a package just with the features you need. There is nothing wrong with using jquery or other libraries. Just be mindful of your target audience, your page size and load times. Optimize images and try not to be dependent on too many plugins.