I also fall into those trivia games every now and then, though sometimes they bore me because they're too basic. What really hooks me more are the ones where they ask you questions about video games or pop culture, those ones have me there for hours without realizing it. Then I open my eyes and half the afternoon has gone by, haha. Your boyfriend has a point that they're addictive, but honestly, it's not like it's the most unproductive thing in the world if you're having fun.
What most people don't see is that those apps are really designed to hook you - the way they give you points, the fire streaks, the competition with others... all that stuff is calculated to make you keep coming back. It's not your fault that you get lost in there, it's that they're made that way on purpose. That said, if your boyfriend complains a lot maybe you could suggest something - like playing some together or setting a time of day without phones. Either way, spending some time on trivia is basically the same as anything else you do on TikTok, so don't feel guilty. People waste time on social media in a million different ways.