Hey Darn,
Thanks for posting! This does make a lot more sense than the previous bug reports. Unlike NoFall, AntiHunger has indeed received major changes in Wurst 7.44 that could affect its behavior with regards to fall damage.
That said, I still couldn't reproduce the issue with the steps you described. What I found is that enabling AntiHunger at high altitude, then falling down, and then disabling AntiHunger, does cause fall damage, but only if NoFall is disabled. Left clicking on blocks, entities, or empty space all had no effect. Same with crouching or mining a block.
It seems like this fall damage bug is caused by something very specific that only some users are doing, but nobody has really figured out what that is yet.
cc @Pylo @LilSkittle