We’ve discussed this previously. Personally, I think Peter was as much older than the other apostles as Arthur Fonzarelli was older than Richard Cunningham.
Peter was older for sure, but I think he was closer than the artists portray. He was still impetuous and quick tempered, like a man in his mid to late 30’s. He supposedly travelled all over the Levant and then to Rome, establishing churches wherever he went, hard work for a young man much less an elder......................