#2. To set up a SmackDown Tag Team title match at Hell in a Cell

In the current story, it's easy to forget that Rey and Dominik Mysterio are SmackDown Tag Team Champions. It would be interesting to see how that match would play out at Hell in a Cell, and whether WWE decides to have a sudden title change before the crowds return full-time.
We've already had one awful Hell in a Cell match in 2019 between 'The Fiend' Bray Wyatt and Seth Rollins, where a non-finish ended the pay-per-view. If WWE has a bizarre finish to the Hell in a Cell match on SmackDown where Rey Mysterio doesn't take a big beating, then he should be ready for a tag team title defense two days later.
Female superstar says she inspired John Cena turning heel HERE
The Usos winning the SmackDown Tag Team Championship at Hell in a Cell wouldn't be a bad thing. It's the final pay-per-view before crowds return to WWE, and they could always extend the angle to a big pay-per-view like SummerSlam so that Rey and Dominik Mysterio get their moment in front of the fans.