Making sure that I’m following this correctly. The steelhead (including native) that are released above the dam/lake to spawn have no way to make it back downstream after spawning?

I’m fully aware not all steelhead choose to spawn in headwaters, as I’ve caught several from crossover down in late January, no eggs remaining, and barely a lick of color of them. I truly believe some fish choose to get in and get out ASAP, maybe as an adaption to the rivers blowing out so frequently now. Why risk staying in the river for 3-5 months while contending with several major rain, silt, and debris events when there may be good side channels in the lower river to spawn?