[zw]

Because you're making mistakes in those other languages? Because the world is not just English anymore, and "going through an i18n library" is all well and good until you need to accept literally any form of user input, which is kind of the point of programming.

> No default indexOf, length, and substring methods?

This makes me think you didn't read the post. There is no lack of those methods. There isn't a one size fits all version, because the problem space isn't generalizable.