They’ve been fixed for a while now. I have used each generation of the new keyboard, and since the 3rd gen (released in 2018) have had exactly zero issues with keys that repeat or fail to register the keystroke.
The feel on the butterfly keyboard is so much better than the older keyboards (which I also use on a regular basis). The amount of travel on the old keys honestly wears my hands down now. I can type forever without fatigue on the newer ones.