Having shot several hundred deer and eaten a good many of those, and I know MANY will argue this, if the meat is properly taken care of and aged for 2-3 days (either in a walk in cooler preferably or on ice with the water draining off), a 7 year old buck shot post rut can taste just as good as a 2 year old shot in October.
But it all boils down to the care of the animal. If you shoot a 2/3/4 year old buck during bow season, make a shot you’re not sure of, wait 3 hours to go look for him, and then find him 45 yards from where you shot him and proceed to cut him up right away and get the meat deboned, he’s not going to taste very good, it’s just science.
Muscle fibers start changing immediately when blood stops pumping and the faster you cool them off while leaving them on the bone, the better quality the meat will be.
Shoot a mature buck at the end of the rut but drop him in his tracks, get him back to camp, gut, skin and in a walk in cooler and leave him for 3 days before breaking him down and the meat will be far better than the one from September.
All this being said, if you can tell me the county you’re hunting in I can tell you when the first and second ruts should peak if you’d care to hunt a particular time frame.