Leather that is really dense with small pores is in general a lot easier to have a shine on, also on areas that moves. The younger the calf is the denser the hide, that’s why this type of leather nowadays usually is called babycalf, even if it was standard calf leather a number of decades ago.
The shoes above from Japanese bespoke shoemaker Main d’Or is made in a vintage box calf hide from the German tannery Freudenberg, and is a really amazing, super dense leather that still isn’t as thin as this type of hides usually are. It’s likely from the 90’s some time, nowadays the tannery doesn’t exist anymore, although recipes and some staff have moved to Poland and the Weinheimer tannery. Not the same stuff as back in the days though, although still good stuff.