U-Boat Flightdeck CAS Black Dial Chronograph Black Leather Mens Watch 6617

So I was wondering, and I would like to hear other's input on this. If the sole purpose of providing a sapphire crystal on a watch is to prevent, and in many cases, eliminate the crystal from being scratched, why is anti-reflective coating applied to its outer surface? I can't seem to understand this. Granted it may provide a higher degree of readability in certain circumstances, but over the long run (years or even decades), it may cause perceivable scratches and imperfections on the crystal........

Need someone to refurb dads Seiko Sportsmatic 7625-8233. Im a lover not a fixer.

This is my 85 year old fathers watch and he just gave it to me to remember him by. His father bought this watch, and two additional ones identical, for him and his two brothers. It was always cool as a young kid getting together and seeing my uncles with the same watch my father had. My father wore it every day for decades until he got an Ironman watch that he could beat up and the Sportsmatic went into a drawer to be passed on to me someday. Dads got Parkinsons and won't be around much longer ........