EK
Just because something is in decline, doesn't mean its not still very useful. jQuery is great for small projects like Chrome extensions which may do a lot of DOM manipulation etc Otherwise you find yourself re-writing functions in vanilla JS that are already available in jQuery. For larger code-bases, projects or libraries/modules, jQuery becomes more like unnecessary and unmanageable bloat. I'd still use jQuery for any smallish project that will need to do a lot of DOM manipulation.