50 years of technology advancement integrated into our beloved 71-73s will surely improve the overall performance in dramatic and imprrssive ways, but then it would not represent a true "50 year old" car anymore.
I refer to my car a "basically stock", but in reality it is nowhere near representative of what was truly a stock vehicle in '71. The following ( some would say) minor upgrades have all teamed together to make my car far more reliable, driveable, enjoyable and dependable than it ever could have been under true "stock" conditions:
1) electronic ignition
2) electronic voltage regulator
3) improved gasket and sealing materials
4) dramatically improved lubricants
5) computer-designed valve train
6) advanced metallurgy in engine components
7) radial tires
8) safer rim design and construction
9) improved brake friction material
10) improved maintenance products
11) improved paint and refinishing technology
12) sound-system technology
13) etc...
These can mostly be considered "invisible" improvements for the most part and really allow the car to still look the part but perform better...but it is really quite an improved machine overall, certainly not indicative of when it was new.
And that is just the minor stuff.
I know my car isn't truly "stock", but the mostly unseen improvements is what I feel has allowed me to actually enjoy and actually use it for 355,000+ miles for over 40 years.