I cannot think of a single common case where grapheme cluster count is important. If you want to print them aligned to a terminal - guess what, double width cha

I cannot think of a single common case where grapheme cluster count is important. If you want to print them aligned to a terminal - guess what, double width characters exist, so the only reliable way is to print them first, measure the cursor movement using escape sequences, calculate length and erase the originally printed data. Even for limiting input field sizes byte count is much better, as otherwise you are opening up yourself for unicode denial of service. I think the game Minecraft has such an exploit where you can fit in absurd amounts of utf-8 data (to the point of data corruption in multiplayer games) since it's limited by visual length. My personal favorite dealing with UTF-8: pretend it's ascii and assume everything above 128 is an alphabetic character. It just works. For 99% of use cases it doesn't matter if the content is emojis, families of emojis, or ancient sumerian scripts. You can parse JSON and most other formats this way without caring about code points at all. The trend of unicodizing everything was a mistake, just treat strings as bytes and parse them as utf-8 only when you really need it (like when building a text editor or a browser engine from scratch).