whither the monarchy

obviously this is not the most important question at the moment but I do wonder what is the point of having a monarch if she can’t swathe herself in ermine and crowns, leap on a white charger, gallop into the House and revoke Article 50 with a swish of her sword while shouting ‘One’s had enough of this balderdash!’ I expect she regrets not beating old Johnson over the head with her handbag when she had the chance