Is Liberty Harbor a nice campground? No.
Is Liberty Harbor a good resort? No.
Is Liberty Harbor the perfect place to enjoy what NYC has to offer? YES!
It is just a large gravel parking lot with services. It is easy to get to with a large RV, it has a large bath house and laundry that is clean. It's location just can't be beat. You could stay at a nice "campground" that is an hour or two away, but then you spend all of your time commuting back and forth instead of enjoying the NYC offerings.
I guess it is just according to what you are looking for. If you want a camping experience, stay elsewhere. If you want a great place to experience the New York offerings, then stay at Liberty Harbor.