Time to call halt to the traditional snaffle bit for horses?

A dog behaviourist once made an interesting statement in a lecture about the widespread use of dog collars We call dogs mans best friends then we tie a noose around their necks and drag them around after us. Some way to treat a friend. She was extolling the virtues of head collars harnesses and other more humane ways of controlling dogs when out on walks.
Similar arguments can be made in the equine world over the use of the traditional snaffle bit which is the conventional way to control a horse.

Anyone who has worked with horses will know how snaffle bits work. The basic construction is a jointed metal bar attached to a metal ring on either side. The reins attach to these rings. The bar sits inside the horses mouth so when the reins are pulled pressure is applied via the bar to the inside of the mouth. The specific area of contact is the part of the gums that have no teeth known as the bars of a horses mouth. This area is between the incisor teeth at the front which are used to pick up food and the molar teeth at the back which grind up the food up before its swallowed. The snaffle bit is meant to be placed just in front of the back teeth. The idea is that the bit does not have direct contact with the teeth instead it places pressure directly on the soft tissue of the gums.
If a horse is well trained the bit is used in a gentle way with very mild pressure passing on the wishes of the rider to the horse in a similar way to a traditional collar being used to guide a well behaved dog.
However if a horse is unruly or if there are other reasons why