This is a bizarre take... Programmers have to deal with a lot of badly written programs all of the time. You'd need this functionality to either debug a progra

This is a bizarre take... Programmers have to deal with a lot of badly written programs all of the time. You'd need this functionality to either debug a program that responds differently to different values of environment variables, or to control it, because, maybe it's the only reasonable way to do so. It's OK to say that programmers shouldn't rely on this functionality ideally, but, for practical reasons, this functionality is needed. Same happens in "pure" functional languages, for example, when you need to debug programs in such languages interactively, and struggle to create the program state that reproduces the problem, or, in some extreme cases, due to I/O being "impure" even struggle to output diagnostic information.