For what it's worth, here's my limit of Skagit River (US) sockeye I caught in July in about an hour, BAR FISHING with a spin-n-glo and shrimp:
Even bar fishing isn't zero impact on sockeye, and I THINK the early season fish are especially susceptible, as they are so long from spawning that they feed more on their way to the spawning grounds. Also, I have seen people flossing with jigs that sit stationary on the river bottom - one element of bar fishing, yet clearly not ethical fishing. There is no easy way to effectively restrict technique that there will be no impact on the low sockeye stocks (or Thompson steelhead and interior coho).
Back in the early 1990s when the sockeye sport fishery first opened on the Fraser, everyone was bottom bouncing with a 2-3 ft leader, just like they had done for pinks for years. I remember being at Island 22 and learning from the old timers how to fish with wool and how to feel the "bite". I don't know if people realized they were flossing, but slowly people figured it out. I didn't actually hear anyone explain what flossing was until at least my 4th sockeye season, when guys started going to 6 foot leaders. Even then, there were times that 3 feet was better, and you only needed to cast out with pencil lead.
I'm amazed that the sport fishery for wild Fraser chinook has lasted this long. In Washington, you generally need to release all unclipped chinook unless you are at a terminal fishery where only an introduced stock is present. Chinook were never the high-volume runs that sockeye and pinks can be, and they are therefore much more susceptible to over-fishing. Add to that the much longer life-cycle, and it makes the runs much harder to bring back.
I'll be curious to see what effect the closure of the SE Alaska chinook fishery has on Fraser returns this fall. I think we should all be grateful that the US bought Alaska from Russia, otherwise they would have fished these stocks to extinction long ago.