As said, pretty much all of these issues would almost certainly be fixable without closing the mountain. The yeti as Martin and other insiders have stated on numerous occasions can be removed and repaired (or given an alternative) without closing the mountain at all. I'm doubtful any downtime would be needed to fix a projector either, regardless of what someone said above.
Despite the shamefulness of Everest's condition, there do still exist refurbs (at least in other parks). One wonders how Splash Mountain and Big Thunder underwent such refurbs that ended up correcting broken or switched off show elements if such things are completely unimportant. Perhaps you should ask Disney why they should fix these issues. To someone in the company, it still does seem to matter somewhat. It hasn't happened to Everest or Animal Kingdom yet, but it's happening in some places elsewhere.