It's fairly irritating. Sometime back while in office I saw a co-worker of mine, a guy in his late 30s rambling about some football match to another. He then asks me if I saw such and such match, and I told him I am more of a tennis fan. He had this look on his face
like he had almost never heard of that sport before. I asked him if he knew about Roger Federer or Nadal , and he gave me this blank stare. He had not even heard of Pete Sampras or Andre Agassi. The only guy he had 'heard' about was McEnroe.
Honestly, after that exchange, I started distancing myself from that guy. I don't care how unpopular a sport tennis is in the US now. How can someone not even have heard of these legendary players??