...there's no physiological reason you would be any more or less stretched out on a 58 versus a 60 with a shorter stem. What counts in this is bar to saddle distance. Saddles are adjustable fore and aft, and even more so if you consider zero setback versus setback posts (available in a variety of setback distances). Bars move fore and aft with changes in stem length (and also a bit with stem angle).

If you measure the (imaginary) linear distance between seat tube top and steerer top (where the stem grabs it) on both, I think you'll find that it is a relatively minor incremental increase with the larger frame.

There are some illustrations you can Google up to see what I'm talking about, usually associated with bike fit articles that show up online.