Also, a lot of this is usage, not grammar.
English spelling is a mess because the printing press and the pronunciation shift happened at around the same time.
Then add in that whole phase people went through in the late 19th century where they pretended English was Latin and made up all kinds of rules that don't actually make any sense in English but people still believe.
(And made up some weird fake latin endings to words, too, because they thought they were cool.)
The fact people refuse to accept that language changes is also a problem.
I mean, no one goes around saying "you can't call a foolish person 'silly' because that's not what it means".