My perspective is as a user / tester. I file bugs and if I know enough to troubleshoot / fix them, I’ll hack on things a bit and gather info. So it doesn’t matter to me whether I file in Bugzilla, Pagure or GitLab. What does matter is whether or not I can get connected with the person who can figure out what’s broken, hopefully with my help.
From that point of view, there are serious problems with Bugzilla due to the size of its database and the number of products it covers. It’s kind of a flawed roach motel - the bugs go in but instead of dying of starvation, they sit there for many releases. They’re sometimes upstream, which may never get acknowledged. They’re often duplicates, the package that demonstrates the symptom may not be the package that’s actually broken, etc.
Given that I’m only minimally interested in Fedora outside of Silverblue, having a separate bug tracker for Silverblue seems like a win, and bonus points for it being easier to use than Bugzilla. On the other hand, maybe I’m hopelessly optimistic, but this strikes me as an opportunity for an artificial intelligence tool that we wouldn’t have if Silverblue had it’s own bug tracker outside of Bugzilla, since nearly all of its components are covered by Bugzilla. There’s a reason people search Google when they get an error message. 