Web developers re-write their entire stack all the time. In a business with tons and tons (and tons) of little apps and services and command line tools etc, NO

Web developers re-write their entire stack all the time. In a business with tons and tons (and tons) of little apps and services and command line tools etc, NO ONE wants to (or can) go through all this stuff to update it because someone decided the way unicode should be handled should change. The value gain to those 100's or little apps and utils is essentially zero. I do think a LOT of people got a lot better at making sure to lock configs down - it used to be you could basically ship the python file and as long as you were not doing something weird the system python / distro python would work fine. Now you really need to version pin everything, because python 3 was a nightmare for all the pip libraries and the knock on effects just showed up everywhere.