While no one wants to see less in their Disney experience, there is a financial view to look at.
Pre-Covid
Disney looked at the non-revenue and revenue-neutral items as an expense.
IF 350,000 people visited the parks in a week and the weekly cost to a line-item like fireworks was $1,000,000 the cost was actually $2.87 per capita
Post Covid
The same fireworks shows are still $1,000,000 per week so it is a fixed expense if 10- people or 350,000 people show up. But if the crown total is now only 100,000 people per week with the reduced attendance, then the same $1,000,000 line item is now being split by only 100,000 guests. Now the per cap price is $10.00 per person. As you add up fixed expenses, the per capita cost goes up with reduced attendance.
Disney has already stated that the parks need to remain cash flow positive, so if you have the same variable per cap costs, but now have higher per cap costs, then something has to give to keep per cap cost below per cap revenue.
The same goes for add-on income like parties. If a party had 30,000 guests pre-covid but will only have 12,000 guests post-covid then the per cap cost of the party is almost triple. So you either have to cut the expense for the party, raise the price of the party (not a good choice in the current economy), or cancel the party. Disney seems to have found a compromise where they have cancelled the party but moved some of the experiences to the day guests.
(note, all numbers and costs are hypothetical, but just as valid for the math)