It probably still is. Consider that in the wild, all the fish that make it back spawn. Some more successfully than others but they all spawn and let nature take its course. That was how the runs evolved. What survived the gauntlet of predators and poor habitat is what spawned; survival of the fittest.

Hatcheries, and intensive mixed stock fisheries changed this. As you noted, fish were selected in the hatchery for artificial reasons; size, color, and maybe even passivity as a passive fish was easier to catch and spawn.

Timing of returns was constrained for convenience, the hook and line fisheries removed the most aggressive feeders, and so on.

Fish were paired for artificial reasons and not natural selection. We now know that jacks and sneaker males contribute; but not in hatcheries.

We need to admit that hatchery fish are radically different from wild. Not better, not worse, but different. We know wild fish do poorly in hatcheries and hatchery fish do poorly in the wild. Well, duh.

Triage in the form of writing off some wild production and some hatchery production is likely the only way to simultaneously retain hatchery and wild fish.