They're both attempts to prevent incumbent carriers from doing bad things. In Net Neutrality, you list the bad things and attempt to prohibit them. In local loop bundling, you make it possible for someone else to provide better service, so there's a competition incentive so the incumbents are less likely to do bad things.

Of course, it's trivial to circumvent either. In net neutrality, you can't deprioritize traffic to someone you don't like, but you can underbuy transit, and setup restrictive peering agreements that only your friends happen to be able to meet. In local loop unbundling, you can sell your retail products for significantly less than the wholesale price (like Pacific Bell did), and make it harder to move services when customers are on an unbundled loop, thus providing an economic and convenience incentive to go with the incumbent. Even still, in this poorly regulationed unbundled loop case, it's economically feasible to get better residential service; in a poorly enforced net neutrality world, you won't necessarily have any real options if you don't want to pay crazy money to connect to dark fiber.