#1 He never lost it back when he retired

Depending on circumstances at a given time, some Superstars have to relinquish a title. Daniel Bryan did it twice last decade when he had to first relinquish the WWE Championship and then the IC title. He had to prematurely retire but was cleared to return a few years later. Becky Lynch even did the same last week with her RAW Women's Championship due to being pregnant.
In those veins, he technically never lost the title to anyonne. Finn Balor had to relinquish the Universal Champion a day after he won it and he used that to eventually get a rematch. WWE did do away with rematches but usually paired the same two Superstars together for three PPV cycles anyways.
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Goldberg said he never got a rematch for the Universal Championship which is why he "challenged" The Fiend earlier this year. Like Brock Lesnar, however, he often goes away once he loses a title. But when a Superstar has to give up a title because of an injury, it's a totally different scenario. It would seem like poetic justice if Daniel Bryan won the IC title for a second time. He never lost it the first time and winning the tournament would be cathartic for his fans and the man himself.