Local translation of websites so you don't have to tell Google about all the sites you want to read that are not in your language. Firefox's address bar that learns what you type most often and moves those items higher in the autocomplete list. There are plenty of great cases for AI very tightly integrated in the browser. That you haven't thought very hard about it or even bothered to see what AI Firefox has already had for ages (Awesomebar was about 15 years ago) is precisely why you don't "get it."