Surely you mean that sorting correctly is impossible without Unicode? Otherwise you would have to hardcode the rules of sorting strings correctly in my language (and all other languages) yourself.
Unless your preferred solution is "close my eyes and prefer non-ascii characters don't exist", then... I'm not a fan.
Case conversion is similar except the default rules do a very good job in general. But still, there are a few language-specific quirks and, again, you do have to know what language is involved to get those right.
I'm agreeing with you, to be clear, just adding that a) Unicode isn't always enough, but it does a decent job if you don't know the language in advance, and that it defines the correct rules if you do know that.
This isn’t necessarily true beyond ASCII, and it depends entirely on the collation [0]. One need only to spend some time peering into the abyss that is RDBMS collation support [1] [2] to see the horror.
[0]: http://www.unicode.org/reports/tr10/
[1]: https://dev.mysql.com/doc/refman/8.4/en/charset-unicode-sets...
How useful this is depends on the language, of course. I did say that as well. But Unicode was put together from legacy character encodings, and did what it could to preserve the order of those, so it's far from useless.