As the popular phrase goes: "It's legacy, all the way down". What matters is what's left of those legacies in current revs.
In both cases: "Quite a bit", but I wish the base Windows OS would evolve away from legacy as much as macOS has. Start with eliminating drive letters.
> Start with eliminating drive letters.
Drive letters are there for the presentation layer and of course backwards compat. Windows refers to them using device paths internally. You can too, if you wish.
https://learn.microsoft.com/en-us/dotnet/standard/io/file-pa...