AFAIK, Grimes did not say ANYTHING about conceal carry. But she did pose with a long gun, like she was some kind of sporting enthusiast.
And she made much of the fact that Mitch walked onstage holding the rifle “upside down”. Actually that is the way you would greet somebody in a friendly way while carrying a long gun. It would be very difficult to aim or fire from such a position.
She should understand that 2A supporters could care less about whether you’re a hunter or sporting enthusiast. Hunting and hobby shooting are irrelevant to the 2A.