#4. The AJ Styles-Omos alliance ran its course
While WWE is notorious for prematurely breaking up tag teams and alliances (example, The Hurt Business), the case of AJ Styles and Omos is different. They didn't have good momentum for months, and after losing the RAW Tag Team titles, they were simply floating in and out of the title picture.
Usually, there is one beneficiary of a tag team breaking up, and in this case, it is expected to be Omos. However, if he gets quickly exposed, then Styles will end up being the beneficiary - something that could happen anyway.
Simply put, the story between the two men had run its course, and with WWE not planning for an AJ Styles world title run, there wasn't much left for them to accomplish. Another tag team title reign would have been monotonous and boring.
If Omos was helping The Phenomenal One with the US title or even the WWE title, it would be understandable. But neither seemed to happen and it was a case of their partnership simply needing to end. WWE timed it well, and there are no complaints about it.