The minute you close a door on them they're caged. No animal should be caged in my view except in exceptional circumstance such as at the vet.
Okay, and what if when they're not 'caged' they mess on the floor, eat things they shouldn't, and become so distressed they cause themselves serious injury?
I mean, you're entitled to your view, but some dogs put themselves in real danger if they're left out of their crates. I've known dogs that will chew electric cables, leap over baby gates, try and eat doors - but when they're shut in their crates, they curl up and fall asleep.
On top of this, what chance does your caged pup have in the event of a break in, or, God forbid a fire.
Both of those circumstances are vanishingly unlikely and not a reason to leave a dog to be distressed out of a crate. If your dog CAN be left loose, then obviously that's great and the best solution, but not all dogs can be left like that.