Without understanding the minutiae of this, couldn’t someone just write a program that we can pipe any output to, which strips colour commands from its input before writing it back out? Does such a program already exist? That wouldn’t require every program to add support for an environment variable.
By itself, less will prevent any control sequences (including colours) from actually being sent to the terminal, but most distros seem to have -R set on it by default these days. If you unset -R it'll do exactly that.
