This has got to be part of it. IMO, most red wine tastes like boots, and while this is anecdotal, everyone I personally know in my age braket agrees. Non-anecdotally though, there’s so many other options for booze out there that are cheaper and it’s never been easier for a person to try multiple things until they find what they like. I personally think wine is so hyped up culturally in the US and the end product is just… spectacularly underwhelming. Like manky water. Why would I get that when I can spend the same money on 2x the volume of a drink I personally like?