Comment by amake

That's fundamental to the mission of Unicode because Unicode is meant to be compatible with all legacy character sets, and those character sets already included combining characters.

So "no combinations" was never going to happen.

That quickly explodes if you need more than one diacritic per letter (e.g. Vietnamese often has two, and then there's https://en.wikipedia.org/wiki/International_Phonetic_Alphabe...).