Indeed, and the title is incorrect too. Function names were not renamed to end up different buckets; Their names were picked that way.

What about usability? "I wasn't too worried about not being able to remember the few function names." certainly indicates that usability decreased. That may have set a pattern for it getting broken, eventually.

This. I was implying that length of the string should mean length in characters, not bytes. This could lead to broken code and would require programmers to keep in mind both.

I have switched from php long ago, but remember odd naming conventions and frequent switch of parameters.