Nearly all forms of sports whether they be physical, electronic, chess, or whatever. From the Superbowl to the Olympics I can't muster up much interest. I do have a fondness for late '90s - early '00s extreme sports games (SSX, Blitz, Tony Hawk, NBA Street etc.).
I don't like most fantasy. LotR, Elder Scrolls, Harry Potter, and Game of Thrones all bore me.
Video games from 2012 - present. I think I'll get back into them eventually though. The games I like are too expensive and time consuming. Free to play and mobile games rarely do anything for me. Major franchises I haven't touched or played just one game from: Zelda, Dragon Quest, Final Fantasy, MGS, Diablo, and probably some more I can't think of.
Never been much into film or anime. I might change this soon.
Most music before 1990. I've got a couple of really popular albums, but there's still a massive trove I've barely scratched the surface of.
Rap music one of only a few forms of media I feel comfortable saying I'm relatively knowledgeable about. There're a still a bunch of niche subcategories in there that I've yet to explore, but I only know they exist because of how much time I've spent listening to and reading about the genre. The other would probably be games. Even though I admit to not playing much in recent years, I still follow the industry more closely than most people.
We're at a point where there's far too much readily available quality entertainment for anyone to truly be up on everything. From now on I'm going to try to pick things that seem interesting and make the time and effort to engage with them rather than just let the backlog pile up. It'll keep growing, but for a long time I was waiting for that perfect opportunity to indulge in my entertainment interests. I realized that time isn't gonna come unless I create it.