#1 Matt Jackson - Competed in WWE over a decade before signing with AEW
Matt Jackson, one half of the former AEW Tag Team Champions, The Young Bucks, had worked with WWE a few times in the past. Well over a decade before the formation of the company, Matt Jackson had a match against legend Big Show.
Big Show was all set to face The Undertaker at Cyber Sunday - the pay-per-view where fan vote directly impacted various factors. In the case of The Undertaker vs Big Show, it was the stipulation.
The three options were a Knockout match, an I Quit match, and a Last Man Standing Match. He demonstrated his ability to compete in all three stipulations by having a succession of the above-stated bouts against enhancement talents.
The Last Man Standing match was against none other than future AEW star Matt Jackson. Unsurprisingly, the match lasted for mere seconds before The Big Show put Matt through a table and won.
The tweet posted above pointed out the irony of Big Show signing with AEW and being "lower" in the hierarchy than Matt Jackson, who is now a big player with The Young Bucks.