hoiking has existed since 1.2, and probably existed longer, but we had no way of finding out about it, which was what, 10 years ago at this point? if they wanted to remove it, they would've done it literally years ago, but decided not to. can you really call it "unintentional" when devs go out of their way to make sure this "unintentional" glitch stays unfixed?
it was the same way with the giants in skyrim, that was never intended, and they did fix it, but had to readd it because it was hilarious.
the creepers were never intended to exist, but notch said "

it, we ball" and decided to leave them in.
if any of these 3 things were intended to be fixed, the devs could easily have done it. and lo and behold, they still exist to this day