Most companies have capital budgets that have to be justified. While we might not like the thought, Disney is a for profit company, not just a creator of Magic. That said, capital spent of DTD can be easily run through financial models to determine ROI based on different scenarios. Risks can be evaluated based on historical data, trends, and research. All of this is done in business concepts that are easily understood by senior management. The results can also be directly measured by the incremental revenue DTD generates. The same is true for building resorts or DVC. Each can be modeled, justified, and ROI tracked independently.
Now contrast that with the parks. What is the ROI for better maintenance of a ride? While preventive maintenance usually costs much less than corrective maintenance, that may not be true if work requires regular closure of rides to fix cosmetic issues. At what point do you hit diminishing returns. What is the ROI of adding a ride to an existing park? While it might add capacity, does the reduced wait times translate directly to increased attendance? Will adding a new themed land draw in new crowds? The fact is, there are allot more unknowns and bigger risks associated with investing in the parks. From a business/financial perspective it is much harder to make a soundly justified decision.
None of this is to justify not spending money on the parks, but the reality is that investing in retail inside and outside of the parks helps to generate the revenue that can then support investment back into the parks.
So whether you like the plans for DTD or not, it's likely easier to secure capital for this project.
Lastly, people tend to think that there is a fixed amount of money available for improvements and that every dollar spent on DTD means one less spent on the parks. That is not necessarily the case. Capital spending is all based on ROI. If a company can invest additional dollars and expect a minimum return based on an reasonable level of risk, it will. An E-ticket ride gets green lit when someone makes a convincing business case. The other complexity is how much does "plussing" a ride add to your return or reduce risk? This creates the issue of doing things "on the cheap". But would spending more money create larger returns?
So I am not trying to justify any decisions made by TDO, but to point out that it is not enough to say Disney should invest more money into X. That has to be backed by what return will that generate for the company. Then, within each project, how much investment is needed to maximize the return or minimize the risk. It's real easy to make these decisions when you are a fan and are not accountable for the results. Try taking your entire life savings and investing it into a single stock for the next 20 years.