One of the big reasons to use jQuery, for a long time, was how easy it made Ajax. It has a super clean, flexible, and cross-browser compatible API for all the Ajax methods. jQuery is still mega popular, but it's becoming more and more common to ditch it, especially as older browser share drops and new browsers have a lot of powerful stuff we used to learn on jQuery for. Even just
querySelectorAll is often cited as a reason to lose the jQuery dependency.
How's Ajax doing?