It’s a reference to an ongoing joke where the Predators organization ended a 2013 letter to season ticket holders with the misspelling, “Go Perds!”
The team embraced it after the fact: https://ftw.usatoday.com/2013/09/nashville-predators-mistakenly-call-team-the-perds
Fans of the Preds use it when the team is playing poorly to voice their displeasure, and fans of opposing teams use it… well, all the time, lol.
Edit: I’m a STH and lifelong fan since day 1… this was one of those you couldn’t help but shake your head, laugh, and roll with it. Self-ownage at its peak.