I would not argue that show quality has dropped, its still lightyears beyond anybody else, which has a weird effect on us of being fantastic and horrible at the same time. We can see the decline, because we obsess over the days when seeing a burned out light bulb was almost unheard of.
What a new person sees is a park that is pristine, compared to anywhere else.
Its a strange thought, but its something Ive noticed with my family travels. Its just a weird situation that we are cursed with from knowing "those days". The other item might not even be a cost issue, but a wear and tear issue...Ive noticed the average guest is just much more destructive than they used to be. Liter, overcrowding, ramming things with strollers/ECV and just general disrespect of the property is fairly common, which causes a day to day destruction that is beyond what used to be normal. Honestly, I fear the number of people WDW would need to hire just to keep up with all the incidental damage done today...There are only so many dents, dings, paint jobs and bulb changes you can get to in an average 8-9 hour down time.