I feel this frustration. I was also on my third year of pounding the trails before I caught my first one. What really helped me was taking the steelheading class at pacific angler with Alex. Literally the first time out fishing after the class I got my first one. My presentations didn't really change but how I fished them and where did. Learning to read the water better was the biggest takeaway for me. I was fishing for them the same as I fished for salmon and it's worth remembering that they are trout. There's a reason the "top rods" are pretty consistent on the river every year. They know the most likely spots in a run that they will be, can pick through them quickly, and move on efficiently. I ended up really loving how much river you tend to cover chasing steelhead vs trying to find a gap on a busy run in salmon season.
Too bad Alex left Pacific Angler. He is now working somewhere else.