a part of me agrees with the aim of what you say: why not start afresh with something that is less prone to accidents? and i do agree with that idea. but i think it is also somewhat impractical to ignore that pretty much every server i've ever interacted with has a default, vanilla, bash installed, and if i know how to use that, it helps me get by.
not to say we can't and shouldn't try to do better.
not to say we can't and shouldn't try to do better.