#2. The crowd would have been drained out for the main event
Having the right people go over is very important in a show like WrestleMania, because if a major crowd favourite loses, then the entire air is sucked out of the stadium. Daniel Bryan winning would have absolutely flattened the crowd and they would not have reacted properly for the matches after that.
The main event of WrestleMania 35 is one of the most important in WWE history for more than just one reason. And WWE needed the crowd to be as hot as possible for that. While the placement of matches on the card were questionable, there's a reason why so many matches were placed in between the WWE Championship match on the main event.
WWE knew that there were a few matches in between that and the main event which the crowd would cool down for, so they had to prioritize. Having Kingston lose would risk the main event.