The parks can be as magical, but with the following caveats. A really crowded day at DL is far more miserable than a really crowded day at WDW. There is only one other park to "hop" to if you want to get out of the Magic Kingdom, and the scale of DL is just so much smaller that when crowds build up past the queue areas that are designed to contain them, they spill out into walking areas that make it almost impossible to maneuver. It can feel like Times Square on New Year's Eve. Wall to wall people. I have experienced "typical" summer days at DL that felt like Code Red (or whatever they call it) days at WDW where they close the parks to additional guests. But an "uncrowded" day at DL is every bit as magical if not more so, when you are in the park.
But it cannot be underestimated what a huge difference there is when you are not in a park. DL has nothing there that can capture the magic of what you can do at WDW after hours and in addition to visiting theme parks. This is especially true when the parks have shorter hours. To us, there is no comparison between a day at WDW and a day at DL when the MK closes at 7:00. At DL, you fight legendary California traffic. At WDW, you go to any number of places to spend several more hours immersed in the magic. Staying on site at DL lessens the blow. But even still. The hotels there are "nice" hotels. But nothing like the theming of the Poly, or the Contemporary, or Animal Kingdom Lodge, or Port Orleans, just to name a few.