If you have ever spent time watching spawning salmon and steelhead in the rivers you would realize that the big bucks almost always win over smaller males. Spawning randomly removes this crucial aspect of natural selection and slows the process down. It has the potential of slowing it down to the point that it has difficulty keeping up or getting ahead of the changing environments. The primary genetic damage that hatcheries do is a result of spawning randomly.

Not sure I understand your sentences. Just get back "more" than nature, especially degrade nature.

Selection of spawners will always be unnatural because the fish will be allowed to choose mates.

Are you also stating that using broodstock native fish for Hatchery production results in a reduction of productivity?