I haven’t seen yet auto-retracting reel but who knows... i do not think it would be good for safety reasons. Let’s say your line gets cut. You have at least partial way out and can try to search other part close to place when it was cut. With auto-reel back once cut all "marked" way out would be lost. Also reel line are quite long so that would require strong spring and quite tension on the line which again would make it more prone to cuts.