He actually explained it on the show today.
In 1997 the Super Bowl was in New Orleans and the Packers beat the Patriots, and his step-dad attended the game and wasn’t a fan of either team, but after the Packers won he brought home a bunch of Packers paraphernalia and Wayne became a fan of them after that. Also explained how at the time in New Orleans it was a joke to be a Saints fan because of how bad they were.
The Saints were a terrible franchise until Drew Brees, so I get not supporting them. They had a decent run in the late 80s/early 90s but they were back to the paper bags soon enough.
It took them 20 years to have a winning season