Note that env::remove_var will still be available, you'll just need to make sure it is safe to call.
And env::remove_var_rust (or whatever the name would end up being) should hopefully make it clear from the name that this is not your usual remove_var operation (unlike the Java API which hides the fact that it acts on a shadow environment).
Not very well... you'll also have to replace all env::var and Command by the versions from that crate, which you might not be able to do if they are not in your code.
I am not suggesting to make it the default. I am suggesting to offering it as a way to port existing code, with documentation clearly calling out that using this is bad style.
