My experience has tended to be the other way round. I’ve filed quite a few bugs in Firefox over the years, and a handful in Chromium. Filtering to similar sorts of reports (since many of my Firefox reports are using-the-browser related, and often dealing with regressions since I’ve used Nightly for ~11 of the last 13 years, whereas my Chromium reports have only ever been for things like rendering errors), most of my Firefox reports have been dealt with fairly promptly (though some linger), whereas in Chromium I don’t think I’ve ever had prompt action after initial triage—a couple have been fixed incidentally two or more years later due to replacement of a large component, but I think that’s it.

(My experience is almost all more than two years old. Haven’t needed to file much in the last couple of years.)