Just pulling a barb back, without careful removal, would have the potential to cause even more damage.

I have not seen one but I do like the idea.

There are retractable barbs on some deer hunting arrows and crossbow bolts. The razors fold in while being carried and flying through the air. They unfold and expand upon impact.

Usually, the fisherman just cuts and files off the barb or buys a barbless hook. To create something so small would make for a weak, easily breakable hook, and not cost effective.