It largely depends on whom you're asking. I think your average Midwest American doesn't know what it is. Or if they do, don't really care for it or like it. Lipton bagged black teas are their standard. Usually served with a lot of sugar and or lemon juice.
Arizona Tea company has a sweetened green tea that has been sold in major grocers and convenience stores for decades. It's very popular and is known for it's cherry blossom motif. I don't want to rag on them because I think they're a decent company, but it's sugar water and green tea might be loosely defined there.
Boba culture has made the younger generations aware of green tea. And they can give you a run for your money when it comes to cultural knowledge. But they would be largely clustered in urban and suburban neighborhoods.
In America, when I see a non-Asian person drinking a boba tea or even a Starbucks Matcha it warms my heart just a little.