Shamelessly stealing this from the Kiwifarms thread about this whole clusterfuck:

The point of the 'AI' bullshit is to allow for some 'fuzzy' search. A typical Recall AI use case involves a typical user vaguely remembering that he found a great video on his new Surface Laptop on PornHub that he remembers as ten bears with the gift barebacking a twink, but searching his Edge browser history for 'ten' 'bears' 'bareback' 'twink' and 'HIV' doesn't find anything. He remembers the cool new feature that the streetshitters added in just for him, and asks Recall AI for "video with ten bears with AIDS barebacking a twink".

The AI is able to do its sophisticated thesaurus-fiddling to realize that what he meant by the query was the video it spent several minutes screenshotting where the window title was "Twelve HUNG DADDIES with rawdog a bugchasing YUNG BOY". Truly a great advance for human science and technology.