I have long arms , legs and I am 6”1.
My chest is meaty and it grows very easily. Including my back. My back is just strong and gets huge regardless of what I do.
For Chest i don’t ever push the bench press. ‘Mainly barbells. I do more reps in the 10-15 range. This puts meat on my chest. I also use time under tension techniques by squeezing and releasing slowly…
I wonder if you can find a way to fully activate the muscle with different chest work. If you don’t feel the chest activating it’s not going to grow.
Shoulders back. Chest out… I also have found decline presses on the machines work well for me. They really activate my chest from that angle. Incline not so much, but I don’t lack in that area of the chest. Cable fly also works really well for me.
I used to push heavy weight on calves and dumbbells. Since I lowered the weights and increased reps I’ve noticed big gains.
These are all ideas that come to mind when I think of my struggle.
I bet the doc will have some interesting answers and guidance for ya.