Magic Kingdom is some distance from the handicap parking spaces. You have to proceed through an underpass to the TTC, then take either the monorail or ferry to the park - so if you're staying onsite, Disney transportation is generally recommended. The spaces still comply with the ADA, including proximity, but they're not especially close.
The other parks, yes. The spots meet the goal of getting the person out of the flow of traffic as safely and quickly as possible.