Ideally, the first person to ever do a thing for a franchise would be a renowned player in franchise history. In the case of the Yankees, a lot of them aren’t really. Founded as the Highlanders in 1903, it took quite a while for the now Yankees franchise to resemble anything close to what they are today. They didn’t appear in the postseason until 1921, and they didn’t break through and win one for two years after that.
The franchise taking so long to truly get going means a lot of the “firsts” in team history are players that are far from household names.