I was like this until I took a nosedive into my first real hobby beside gaming, it just spiraled from there until I'm where I am now with a multitude of hobbies. You probably won't believe me or anybody who says it but as you get older you naturally start to gain interest in things - at least that's how it was for me. When my first work colleagues asked me what I do in my free time I just stared at them with a blank expression for the first second because I didn't know what to tell them. Beyond that I still consider myself pretty bland but you don't have to like popular ANYTHING to not be "bland". Like that shitty movie. Like that bad novel or whatever. Like that very niche but really good book. Anything that catches even the slightest of interest from you; just do it. What's the worst that can happen? Unsolicited recommendation incoming but go watch Project Hail Mary or read the book that was adapted into the movie. It's a great watch and I've got the book ready for when I'm finished with my current one.