NotEnoughKeys hasn't been maintained since the Minecraft 1.8 days, and as such I think the integration should be removed from the code. I don't think it's worth it to leave what's left of the integration in the code since NEK is pretty much dead.

Yes, it got replaced by https://minecraft.curseforge.com/projects/controlling (in terms of community adaption)

And since that needs no integration
(EDIT: Link to github: https://github.com/jaredlll08/Controlling for future reference)

Yep, I'm on board with that :)

NEK code has been removed in this build.