Comment by sigmoid10

I have wanted string length many times in production systems for language processing. And it is perfectly fine as long as whatever you are using is consistent. I rarely care how many bytes an emoji actually is unless I'm worried about extreme efficiency in storage or how many monospace characters it uses unless I do very specific UI things. This blog is more of a cautionary tale what can happen if you unconsciously mix standards e.g. by using one in the backend and another in the frontend. But this is not a problem of string lengths per se, they are just one instance where modern implementations are all over the place.