Here is my take.
It was a combo of presentation / change offering often.
The deal with fishing amoungst a crowded section that held plenty of fish you really had to keep on top of the game .
If one was hanging up often with little control of the drift it became a hail mary attempt at hooking fish.
If one kept control of their fly amoungst all the other fishermen it became a match what they would take. Not as many hooked but the take was felt.
Things happened in this fall steelhead game we played.
Older more resident fish were always there. That's when a constant change of fly was required to find what they will take assuming your presentation is correct.
Every so often a new pod of fresh fish ( transition) mostly chrome would come through . That's when anything you threw in their sight would work.
Soon it will become a winter fishery and repetitive presentation with control not just dredging , along with finding what will trigger a take will happen . Dredging without control of the line will only result in hook ups not takes.