From the OP, it seems the filters don't flag CSAM. They flag any NSFW. That said, keep in mind that the filter would also have false negatives, so if people want to slip NSFW though, they might be able to do it through the filter even without such option.
But I don't mind the content staying hidden until a mod reviewed is in such cases. The false positive rate of the filter would likely be small, so there wouldn't be too many things that need review.
Actually, reporting issues is not considered a bad practice in open source. If the corporation expects the dev to work for free, that's a problem. But I found the original bug report, and it's just a normal report. It doesn't read entitled, doesn't demand "Fix it NOW!!!", simply explains an issue.