I don't hate Fosse's "Cabaret" the way Christopher Isherwood did, I just don't think it's a very good film.
Fosse was a genius of the American stage but unfocused as a filmmaker. I think part of the problem with Fosse's films is that he entered the world of movie making when the studio system was dying and the French and Italian New Wave was at the peak of its influence. So that meant that Fosse had a great deal of freedom with what to do with camera, lighting and cutting but I think he would have better benefitted from the more conservative but more coherant studio technician style... to give his films a stronger internal spine.
"Clueless" on the other hand uses the feature film format to tell a very coherant story. Cher Howowitz is convinced that her view of the world is the only one. Because Cher acts cluelessly on that assumption, it causes her view of the world to start to crack. Through the cracks, Cher starts to realize other people and their views make up the world. And that realization allows her to triumph in love.
That's basically the Jane Austen story the film is adapted from. But it seems to me also to be a very American story and somewhat dark under its silly surface as many of us never reach Cher's realization.