In regards to those prices, you are talking about wildlife, not livestock. So cows, chickens, sheep, pigs etc. don't fall under that category. It depends on the region, but overall seen in the Western world there isn't that much wildlife on the menu as we primarily eat livestock. Yes wildlife can be on the menu, but by default that's already quite expensive and is largely eaten by people who already have money. So I doubt that the disappearance of wildlife will increase the price of our regular meat, at least not directly. You could even theorize it would go down as one of the primary reasons wildlife diminishes is because humans take over their natural habitat for farming and livestock. So less wildlife means more territories, more livestock and thus lower meat prizes.
I'm not talking about fish though as that's a separate case.
