Of course. They're a theme park. Their business is building new attractions.
What is the alternative? Lower prices, stop spending and hope that people keep coming for new popcorn buckets? That high volume business model certainly can work, and worked for a great many years, but they pretty much hit the ceiling on what the parks could support and couldn't show any growth going forward without a reset.
I think they will be fine. If you imagine that their pricing and offerings are on a sliding scale between high prices and more offerings, and low prices and low offerings, they will always end up putting out one group or the other.
I'm absolutely convinced that the people who say "they need to add more shows" are the ones secretly hoping everyone else goes to those shows so the attraction lines are shorter for themselves.
The parties are not a reason why people stopped going. They are well attended and prove that people want to pay more for lower crowds and a better experience.
Offering a two-tier model is a compromise that works for them. They can have "regular" park hours with a busier park for a reduced rate, or a premium experience for a higher rate. People get to choose the experience they want or can afford.
Same goes for Lightning Lane. They could raise prices and lower attendance to a point where Lightning Lane isn't needed, but that would price out more people.
Some people want to go and pay the absolute minimum necessary. But you can't keep a premium product on that model.