It's amazing how one can go from the longest title defense streak in the UFC (11) to being considered as overthrown instantly as soon as another guy gets his first defense.
Even if you think DJ's opponents weren't worth shit, and a win over TJ is better than all of them, you must consider how important longevity is when naming the GOAT.
Two title wins in a short time can never trump 11 title fights over many years.
Also consider that DJ's record will always be somewhat underrated - since he never had the opportunity to beat a flyweight champ, like Cejudo did.
The only way that DJ could've beaten a respected flyweight would be if he lost his title and won the rematch. (Like if he returned now)