Where did you get the idea that it was removed since 1.3? bhopping was the main thing I found enjoyable to do and I’ve only played 1.5+. Definitely I was there until 1.6 which is the latest version.
Pre-CS1.3 bunnyhopping worked the same as Quake. People soon figured out CS-style bunnyhopping, and it’s hard enough that Valve didn’t bother nerfing it again