I've recently started using Pro for some processes I've done hundreds of times. After investigating some unexplained changes in the hundredth decimal place of some DMS coordinates I decided to compare Map vs. Pro calculate geometry results for some coordinates. Same shapefile, same geographic coordinate system NAD 83 (1986, the original one), no projection. The difference bewteen Map and Pro for the first coordinate pair longitude is 55.831" versus 55.843", similar results for the other coordinates as below with MAP being the ArcMap results and Pro being the Pro results.

Am I missing something or is this a bug with Pro's calculate geometry?