Chael went from the boring wrestler who was best known for getting submitted from guard in every single big fight he had.
Only when he started cutting WWE promos did people notice him. Colby is following in his footsteps, except he isn't charismatic, clever, or funny like Chael was so he has to go for pure shock value.
It's sad that this is what sells, but there is no denying it. I don't blame any fighter for trying. Literally nobody would be fans of these guys if they just kept quiet and came in the octagon to grind their opponents to a decision. Some guys don't need to talk because they have flashy KO's or subs, or a certain look or something like that. These guys are boring in every way imaginable, so their options are toil on the undercard forever or start talking trash. Look at where Chael's gimmick got him. That wasn't fighting talent... sure he had a stretch where he was a top 3 middleweight, but that's about all he did in the cage that was notable. It's what he did outside that made him successful, Colby will be the same way.