>>8people like you critique conio.h without understanding its purpose and appeal. It is a minimal header that allows console functionality not exposed by C standard, which is highly useful for text input/output.
Curses/ncurses libraries implement the same functionality, which is very useful in Unix world. I doubt you would critique a book if it was about ncurses, because in your worldview Unix=good,windows=bad and by association getch() in ncurses is good and getch() in conio is bad(the minority of mac/lunix users on the planet might complain about "cross-platformness" while ignoring the largest platform). If you look past the abstraction, the real code is using the same functionality implemented differently. Conio is just windows specific and doesn't require any special handling, just plain function calls unlike curses which need to be properly initialized and handled, not to mention having much more internal state and code size. Conio beats curses by simplicity and ease of use, which are sought for by people who want minimum dependencies and cruft to include in their programs. The appeal of conio is not because of some standard or mandate to use, it because its useful and simple.
Reducing or removing conio doesn't solve anything(as mingw maintainers think) and people wouldn't automatically start using curses libraries, just because they need a single getch function.