So, there's two ways to look at this, either you go with the approach that will support the most users and let the other's suffer (or degrade gracefully, ideally). Or write a bunch of boilerplate code to support browsers. Luckily, the second option is actually viable. There's a plethora of libraries other people have taken the time to write for you. These are great. They are well tested, cross-browser and are really easy to use.
The problem is that sometimes you have to add 9595 lines of codes just to do something as simple as
I personally think that soon enough, we won't need jQuery to do as much for us, with new browser APIs it gets increasingly easier to get things done with less. Things like querySelectors and CSS3 animations can go a long way when building a modern site. But, as long as we have money to be made and time to be saved and many browsers to be supported, going vanilla might not be a good option in most cases.
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