[maximumoverload]

The main issue is, I think - if something works, nobody wants to fix it. Especially if that something is full with 80s code.

Bash works, pretty well, for a lot of people. So nobody wants to touch it.

[TheCondor]

Ironically, the shit is free, fork it and have at it! Contribute fixes... "Security guys" don't do that though, do they?

There are a whole lot of really important pieces of code that not a lot of people find sexy to work on.

[maximumoverload]

Yeah, but it works already, and there are also so many features it's hard to know what all could be broken by randomly fiddling around the code.

(I suppose bash does not have a test suite.)