I don't think "Other companies have made fraudulent claims too" is a valid defense. The federal government choosing to go after a company that has delivered on less of its claims seems reasonable given limited resources to prosecute this sort of thing.

Especially as Tesla has done a great job of going right up to the border on misleading claims, and even stepped its toes over the line a bit, but not in a way that would be as easy to prosecute as the more blatant Nikola.