It's not so much that you would be denied. It's that the area near the castle is roped off. You can't even get there. At WDW the entire area on Main Street, including right up to the castle, is open. That's because early breakfast in the castle is offered there. At DL, only Plaza Inn offers early breakfast (not sure about Carnation Cafe, but it's even further back on Main Street) so there's a rope across Main Street near the restaurant.
We always do early entry, and I wouldn't count on great photos then. Too many guests flooding Main Street toward the castle at the same time. Our best shots were about 30 minutes into early entry when everyone is already where they planned to be, and the regular entry crowd isn't in the park yet.
We took this one just over a week ago around 30 minutes into the 7 AM early open.
IMG_4543 by
mom2rtk, on Flickr