Obviously 2 inches is a lot to this Dickensonian old codger. Give it back to him or else be covered with perpetuall geriatric treacle.
Have you ever lived next to a neighbor who has taken 2 inches of your land down the entire property line? They tend to smirk and ask what is the big deal? If the position were reversed the smirking neighbor would cry a different tune.
Let’s say this is true. Can the old codger take off 2 inches of the wall. Smirking neighbor wouldn’t be too happy, and neither would the court system. If I were the judge in this case, and it were proved to be true, then an order for certain amount of “rent” money (adjusted for inflation) would be paid annually by the encroaching neighbor until the year after the wall comes down. And if the neighbor does not pay it, the old codger may put a lien on the neighbor’s property, and encroacher is responsible for the old codger’s legal fees should it be necessary to enforce his rights. Bet Mr Smirking-What’s-The-Big-Deal?-Neighbor won’t be so happy, and old codger, well ...
(PS - I was President of an HOA for many years. I can tell you stories about feuding neighbors, etc. Hard to believe adults act in this manner - disrespecting others’ property is very common. HOA had a restriction that approved fences had to be set back one foot from the property line ... to avoid situations like this one. I No longer live in an HOA neighborhood.)