Please allow me to add my perspective on soft hackles.
If you mean soft hackles as in traditional, classic wet flies, they are extremely effective and versatile flies. They have been around and worked for more than a hundred years and will continue to work well into the future.
Soft hackles are just that, soft hackles. The tying secret is no more than 2 turns for the collar. Soft hackles move in the water and create life so you want sparseness. The movement could be legs, could be wings, could be gills, it could be anything. Too many turns and you defeat the reason why they are effective.
A wet fly swing is very effective, especially on waters that see good caddis hatches. Most caddis hatch underwater and dart upwards against the current to break the surface and emerge. That darting movement is what the wet fly swing imitates and that darting movement becomes ingrained in the trout’s memory and that’s why fishing a wet fly swing during periods of no hatch catches fish.
Weighting a wet fly and fishing it closer to the bottom imitates many things from a cased caddis to a mayfly nymph to a stonefly nymph to maybe even a cressbug or scud.
Wet flies make excellent emergers or cripples you just need a dry fly desiccant like Frog’s Fanny to recondition the fly after every 5-6 casts so it continues to float. If you use an actual floatant use a spray type floatant and not a gel floatant like Gink, as the gel will actually cause the fly to sink. To improve floatability you can substitute stiffer dry fly hackles but still tie the collar wet fly style. The stiffer barbs will be more resilient to becoming water logged and sinking.
Fishing wet flies is a long gone forgotten method that many do not use but those that use it are generally the very successful trout fishermen.