When I raid, I always get offered opponents in the 4400+ TP range. My defence is 4200 or so. My attack teams considerably lower. Even when I slip down around 2300-2400 cups that’s the range of my opponents. So, yeah the game does skew towards the upper range in who it offers you. It is what it is.
It also depends a lot on your defence team. For the longest time my tank was Marjana, and I would tumble 400 cups if I ventured above 2600. Now with Justice tank I can maintain above 2400, closer to 2500, even venturing around 2700.