An auto-inflate hose makes control at the touch of your hand. After an exhausting dive it can be difficult to blow up your BC on the surface in a big chop. This is not true in calm water after an easy dive but managing risk means you can do the task in difficult conditions. Some commercial divers dive without a BC because they feel it is bulky, in the way of doing their task, and an entrapment risk because it may catch on something. These reasons don't apply to recreational diving because we are not usually doing a task in a confined space.
Commercial divers have life lines and communication.
We do not. The disadvantage is that it pushes your face down into the water when it is fully inflated on the surface. Look for a balance between what is easy and what meets the need on the dive. Ask yourself if you need the extra piece for that specific dive. For example, have your knife strapped to the inside of your leg rather than the outside.