#1 Vince McMahon's original plan for Roman Reigns
Some fans may have forgotten that Vince McMahon's original plans for Roman Reigns at WrestleMania 36 was for him to win the Universal Title. WWE even went through the trouble of having The Fiend drop it to Goldberg in order to make it a bigger match, which only angered fans.
Roman Reigns eventually made the decision to drop out of the match due to concerns over COVID-19 and went on to take a four-month hiatus from the company. This left WWE with little choice but to put Braun Strowman in his place and give the title to him instead.
Roman Reigns attacking The Fiend and Braun Strowman, and the subsequent announcement of a triple threat match at Payback, seems to point towards WWE wanting to go forward with this plan. Either that or the company is trying to cram a triple threat match in to make Payback a box office draw, and have no intention of doing something meaningful.