Let's Go Brandon!
Well, that is definitely the issue!! One that I dare to say can be reversed for sure. I hurt my shoulder in the late 90's doing heavy close grip bench press. Had chronic pain for about 10 years... regular bench press would bother me but I could still do dumbbells without any issues... working overhead would kill me after a short time (I own a plumbing/electric company so that's a common thing for me to do)... anyway... I started doing a lot of calisthenics/gymnastics style training in 2007. In less than a year that pain was minimal... not long after and to this day gone for good... and I still train very hard... like working the human flag and things like front and back levers and tons of other shit.It wasn't an organized activity. I'd be at the playground, running the ladders and rings and eventually end up hanging from the horizontal bars.
I didn't think it was anything special. Never dawned on me that my friends couldn't do it.
I can point you in the right direction of a lot of people to follow on YouTube and Instagram if you're interested...