Unfortunately vanilla JS is much less readable. JQuery function names make your intent very clear and chaining them is elegant. Also, very minor, but the "magic" (syntactic sugar) provided by `$()` compared to `document.querySelectorAll()` et al. makes using JQuery seem much more frictionless, especially since you know if you're using it, all the functions will work on whatever you selected and can also take HTML strings, etc.

One thing vanilla JS does have going for it though is performance. I profiled a script of mine and rewrote all the bottlenecks using native JS and it's undoubtedly faster.

And many projects/people don't care about not supporting anything but the latest chrome, so yes, for them it's a legacy.