The problem with being concerned about hearing about effects that are down rising is because you don't hear about things that are working and you don't know how long something is down or when it happened and why it happened. We all hear about more stuff being down just because of discussion boards like this one. That doesn't necessarily mean that more thing break now then they did before. We are hearing about a moment in time and that is all. An hour later it might have been fixed or it might be something that has to wait until the park is closed for the night. It really means nothing. What is important is what we, individually see when we are there not what we hear about. One thing we can count on is when it comes to social media, exaggeration is a huge part of it.
Not everything is worth fixing. In this case Everest (Yeti) is not missed by anyone except those that knew it ever existed. There are times when the cost vastly exceeds the return. That was one of those Items. If you have an older daily driver of a car that needs the radio fixed, do you spare no expense to fix it immediately or do you do it when you get either the time or the money or the need to fix it. There is also sometimes that the owner/provider of the broken item just doesn't want to fix it for what could be a thousand reasons all of which are up to them to do or not to do. We have no control other than just refusing to pay them for your presence.
And the fact that more effects are down completely justifies saying that as things get older they require more maintenance and a lot of things in WDW, which just celebrated its 50th birthday, is no exception. The main thing is yes, there may be a lot of things that we see broken, but we are just there a fraction of the time that those things have existed. We might see things that just broke that day before we saw it, there might be other things that require ordering and waiting for parts. Yes, I know the old argument that if it's broken they should close the attraction down. Then, of course, we get the crowd that will whine like someone just made a your Mother joke because they saved all year and when they got there their favorite ride was closed down because one of the minor effects was broken. In this day and age it really is a waste of needed places for crowds to fan out. Other things might just be a matter of priority. The parks are open probably 12 plus hours a day and there are four big parks that all need overnight maintenance, not everything is of equal importance. The most important is done first. Anything dealing with safety must have top priority and having an animatronic not make the move as it should is not really a top of the list item. That is a as soon as we get time item.