I've seen some who've had such issues with top surgery after long term binding. Like the chest post-op can get uneven in shape and/or colour, and scars can stretch more if the skin around is less elastic as it pulls more at the scars when moving then. Most or a lot of the skin above the nipples will likely still be on the chest post-op, depending on the cup size and how far down nipples are. With the double incision method, that is. The only skin that was removed from my chest was that which was between my nipples and where it stop underneath those humps, if that makes sense.
I was binding for around 5 years before my top surgery. Before binding my tits were very round and firm, like they looked fake, but I can assure you they were not!
After those 5 years of binding, they sagged more but looked more like average tits of that size (B-C-cup) and their skin was still quite elastic and didn't look bad. The only thing about my binding that affected my top surgery result was a dent in my ribs that I had unknowingly caused. It's a quite small dent though, and I didn't notice it until after my op.
I used the same binder through that entire time of binding cause it was adjustable and never wore out, but I've later on heard that is not a good type of binder or company. It was a mid-length one with velcro on one side from T-Kingdom. Might be the reason I dented my ribs, or it was the frequency or the length of time, or who knows what.
One more thing about skin elasticity, is that it's also very related to age. Meaning for those who are older, the skin will be less elastic simply due to age, and adding on binding to that might be of some concern. For us younger guys, skin is generally more elastic. I was 24 when I had my top surgery, which is young in that sense. I don't know at what kind of age skin elasticity may generally start getting noticably worse, but maybe possibly somewhere around middle age.
