Depends on the use (imo)
I think for self extraction or extracting others with extraction points, a thimble is pretty cool.
For those who do a lot of general purpose work (clearing property, moving logs off a trail, moving dead vehicles, etc) or work with chains, a hook is hard to beat because it is so fast to use.
I use hooks on both my winches (one with synthetic, the other with wire rope), because the majority of what I'm doing is not extractions.
I also like to keep a bit of rope out loose from the fairlead, like in this picture below, so that it doesn't bind up the clutch. But again, this is more a personal choice for speed.
So for someone who will use their winch once in a blue moon, if they or someone else gets stuck, my thought is the thimble is a pretty cool tool. Slowing down and paying attention to safety by being forced to use bow rings, is a good thing.
For those who work their winches consistently, a hook is going to make life easier.
But that is just my personal opinion.