Upper and lower codepoints are really way too obscure and can create issues you didn't even know you had. I once had the very unpleasant experience of debuggin

Upper and lower codepoints are really way too obscure and can create issues you didn't even know you had. I once had the very unpleasant experience of debugging a case where data saved with R on windows and loaded on macOS ended up with individually double-encoded codepoints. Not fun.