I just explicitly put the P.O. name back in the name field. Otherwise, the OSM website interface shows no name at all on the post office, just the icon. This is the main post office for the zip code, so it merits its name being seen.

There are a couple post offices further south in the UWS that I think the names are missing, but they may be places that relocated into newer buildings. The Ansonia station for example is about 4 blocks from the Ansonia.