Virtual I think is the spelling, I generally agree but do remember that a "traditional" quill stems placed the handlebar differently than the current stem design trends, basically a new lugged steel frame today designed for modern components, even with a horizontal top tube will probably have an extension to the lug to make up the difference. With exceptions noted, on average, top tubes today are shorter and stems longer than in the 60's or 70's. I am not so sure this is a good thing, just different.

Also note that handlebars are wider today, 40cm ctc was very common 30 years ago, 42 for the "big boys" 44cm traditional bars were made but not till the 80's. A guy who rode a 40cm bar in years gone by would be placed on a 42cm or wider bar today.

In the 50's and prior for reference, 36cm or 38cm was common. Some conjecture, some fashion, some validated analysis increased the width.

I won't even discuss crank length and position behind the BB...

My bet though, if you are on a 53cm frame today, you will probably be on a 55 to 57 "traditional" frame.