Poor performance isn’t typically a “bad thing” in this sense. For instance, if someone went and pissed in the coffee pot, they would be fired. If a big group of people were simply told to not come in anymore it’s laid off. Tesla specifically said this wasn’t laying people off so I’m not sure how that works.

I don’t know if there’s any legal or contractual grounds for one or the other but I’d guess it would matter what state you’re in.

I know for a lot of states collecting unemployment benefits does require some sort of reason for termination that is related to the above distinction.