This probably deserves it's own thread but I see that as the main problem. The short staffing and over crowding to squeeze out some cash has a negative effect on the cast members who have to deal with the problem. This in turns makes the cast members less than "magical". It taxes and wears on them. What you are left with is lower customer service and quality.
The biggest asset of Disney IMO has never been the rides but the happy, magical atmosphere that is created by the "happy" cast members and that in turn is infectious to the crowds. Walt Disney understood this.
You take away that and then there's nothing to differentiate it from Six Flags or other regional parks. The magical, happy atmosphere is what has always given Disney an edge over everyone else.
The mistake Disney is making is thinking that the rides and lands at Universal (through Harry Potter) are what has elevated Universal. What has made Universal popular is that Harry Potter captures that same happy, "magical" feeling that Universal always lacked.
Any new ride or area will have an initial draw but what will keep people coming back is that customer service, "magic' and quality. You can't do that when you cut corners, make it obvious you are pinching every dollar, and lower the morale of the cast members through over crowding and short staffing.