My chest would never grow, It was always simply just puny, even at 300lbs and D-cup sized man boobs the muscle under it was non-existant.
Everything I did, helped the rest of my body except my chest. HST helped thicken it up a little but not much (3x weekly flat
barbell bench press).
Now it's doing a little better still, nothing impressive about it, never will be...but I'm doing something just a little different.
2x weekly
flat barbell bench press. Five ramped sets of five reps on Monday. Friday is a repeat of sets 1-4 from Monday then for set 5, I do a 2.5% increase in weight from Monday's last set but only do 3 reps. Come Monday, I go for my 3 rep weight but do 5 reps.
My 5RM is reached at the end of week 4 but I keep increasing the weight every week and get a new 5RM. When it stalls and I can't go farther, I reset the program so that my 5RM is again at week 4 and ride it as far as it takes me again.
Helped me some. Maybe it'll help you, maybe not. Worth considering at least.