So, I wanted to address this a while back, but time was not on my side. 
I love Disney fireworks, and this gallery probably proves that along with the rest of my other Disney galleries dedicated to fireworks. However, one issue that arises with these new shows is the disconnect of those who are in charge of creating the shows, and the visual experience of the viewer.
Human eye cannot process both projections and fireworks at the same time, or long enough to be able to enjoy both. So, you either have to watch the projections, or the fireworks. I am not speaking for myself because I only care about the fireworks, and I never look at the Castle to see the projections 'during' the fireworks.
Not sure if anyone remembers, but Celebrate The Magic was a great projection mapping show! I personally miss it a lot because the music selected was beautifully synchronized, and the projections were amazing. The holiday version of that show was awesome too. The greatness of it came from being able to truly enjoy the new tech of projection mapping without being distracted by anything else. (Not even the annoying habit of some who put their kids on their shoulders 🤦‍♀️). 
Now though, people are expected to enjoy these ADHD inducing fireworks shows, and after a day full of dealing with heat and screaming kids; No one needs this kind of disturbing visual stimulation that late in the evening. 
Originally, the point of the "fireworks" was to close a day full of all sorts of fun! It was the culmination of a day full of meeting characters, seeing shows, ride the many different attractions etc., and it was a great way to end the day. 15 minutes was more than enough. Now, those who've never been no longer have that option because they can't really fully enjoy the fireworks shows thanks to the projections constantly changing and distracting them. Or the water displays, projections, and fireworks with the new Harmonious at Epcot. (The barges are also destroying the appearance of the park during the day!) 
They are all a visual Jambalaya now, and it's sad. It takes away from the overall experience when you don't know where to look. If you look at the projections you're sure to miss the fireworks and vice versa. I understand the need for "new" and/or taking advantage of technical advancements in offerings, but this is a downgrade in the visual "experience". 
My son who's on the Autism spectrum cannot enjoy these shows anymore. He goes on rides during the fireworks now, because the 'visual stimulation' is now too much for him, and he enjoyed Wishes, Hallowishes, and Illuminations more than I can explain it into words here. He enjoyed those shows so much because the "story" portion was handled with amazing care and professionalism, and the music was perfectly synchronized with the fireworks displays as well. Now the synchronization has gone the way of the dinosaurs, and this cramming of every possible movie into these fireworks shows turned them into a visual disturbance. 
My son shared this video below, and I think it's right on the money as to what has happened to this 50th Celebration. I think Walt would have been utterly disappointed. It seems like everything happening there now is only a way to maintain the CEO's 60 million dollar a year salary with total disregard to the consumers who pay through the nose to visit, and support that ridiculous salary. Mickey's Not So Scary Halloween Party is prime example of the greed and disconnect in regards to customer expectations. Now, the price has gone up to over $129 per person, and there's no Hocus Pocus, no Boo To You Parade, no Hallowishes, and no character meet and greets. So, basically a major rip off, and the sad part is that people refuse to pay attention and allow this company to continuously bankrupt their visitors both money wise and through experiences. The ride re-purposing also contributes to the downfall of these parks, and it's really disappointing that Disney just doesn't care anymore.
It would be nice if they tried to use empathy, and see these shows and attractions as their visitors do.

Notice all the people's phones; These folks are distracted by projections, fireworks, and the recording of the show, plus their kids. These people have zero opportunity at truly enjoying this fireworks show.

Same here. People trying to mitigate the projections, water works, and the fireworks.