Slightly off-topic, but as much as I love ncdu and install it everywhere, I wish it didn't need to exist! By this I mean: why are both Windows Explorer and all

Slightly off-topic, but as much as I love ncdu and install it everywhere, I wish it didn't need to exist! By this I mean: why are both Windows Explorer and all major Linux file managers incapable of showing total recursive directory size in bytes the same way OS X's Finder can? ncdu traverses home folders very quickly, why can't this be built in to a GUI file manager as an option, as Finder's Calculate All Sizes is? I cannot be the only user for whom this is an absolutely indispensable feature --- one that actually keeps me from migrating entirely to Linux.