mount
you immediately see what I mean. Stuff that should be hidden is now in plain sight, and destroys the usefulness of simple system commands. And worse, the user can fiddle with the data structures. It's like giving the user peek and poke commands.The idea of containers is nice, but they are a hack until kernels are re-architected.
findmnt --real
It's part of linux-utils, so it is generally available wherever have a shell. The legacy tools you have in mind aren't ever going to be changed as you would wish, for reasons.