Spotted...

I can be as tall as you, but if my legs are longer or the arms are shorter then obviously we'll need different size stem, longer/shorter seatpost, different setback to the saddle. My wife is much shorter than me although her arms are quite long because she's black. It's all about the proportions.
Hence you've got "square" frames or those with longer/shorter top tube etc.

As long as the rider is comfortable on his ride! and makes it his own !! and of course rides it.