"Broken" is a subjective thing, but quirks that break extremely well established patterns (like how people validate the beginning and end of a line in regex) is where a lot of security issues tend to crop up.

Considering that I would venture to say that this is indeed a broken thing since it's a convention that I've only heard about in Ruby. It's a special snowflake in a component that developers use almost exclusively for validation (regex), with a pretty huge gotcha, especially because it appears to function as intended.