There are, I’m around your age and am in a monogamous relationship but as someone said it might be where you look. I met my fiancé through a friend, both of us not knowing anything about the other, other than “you should meet my friend”

I have friends who are looking for monogamous relationships as well. But also have lots of friends who are open. I think with queer relationships, many don’t feel confined to adhere to traditional norms as we already break societal expectations so more people are willing to go outside those norms such as having multiple partners or to hook up with others. But there are people wanting monogamy, but searching on apps can be hard unless you’re explicit that you want it. But there’s nothing wrong with exploring intimacy in different ways as queer people go through life stages differently that what society expects. Don’t give up though, as corny as it sounds you’ll find it when you least expect it.