He could be the HW champ yes but I don't think he would be able to rule the division. I think he'd really struggle with big and athletic guys like Miocic and JDS or someone with excellent ground game like Werdum. He's a good HW, we've already seen that, but we haven't seen him fight elite HWs or athletic HWs that have good striking and TDD (Barnett and Bigfoot don't really count nowadays). Cormier would be a legit top 10 HW but I would probably bet against him if he fought a top 5 HW.