*ahem* Disco Yeti was an extremely ambitious animatronic that unfortunately did not pan out. The strain on the ride infrastructure and the mountain's general support structure was too great with the animatronic operational and due to the interconnected nature of construction it would effectively require a rebuild of the entire thing to get up and running again, which is not happening for obvious reasons. Similar to the
falling rocks effect in the Temple of the Forbidden eye this was a case of the Imagineers being a little too ambitious with their plans. Which, of course, we generally want to encourage as most of the time it works out.
A single projector malfunction is unfortunate to be sure but not the kind of thing Disney will leave around for long. Though if they were to leave it out of commission at any of their parks, it would probably be Paris