Was a mistake #2: He was the first Cruiserweight champion of the modern era
When you're trying to build up a legacy, it's important to have a sense of history. For example, the WWE is fond of mentioning that Pat Patterson was the first ever Intercontinental champion in company history.
Bayley and Sasha Banks likewise made history as the Boss n Hug connection managed to capture the WWE women's tag team titles at Elimination Chamber.
But when the time comes to list the lineage of the Cruiserweight title, it's quite likely that TJ Perkins will be working or will have worked for a rival promotion. The WWE loathe to mention superstars who no longer work for them--look how quickly Chris Jericho was snubbed from the intro to their programming after he signed with All Elite Wrestling--and leaving out any mention of TJ Perkins will feel weird because he was the first ever Cruiserweight champion.