I think they could be "dangerous" if that's interpreted as "dangerous for everyone on the field including themselves". I don't think the defense is likely to sustain strong play against playoff competition consistently. The Bills game could be telling in that way.
But I've always said: get Joe Burrow to the dance, and you have a chance. No rhyme intended.
Unfortunately, given that I will not tinker with playoff machines, the Bengals current probability for a playoff berth is 0%. Woo! Let's get some cheap wins for the sake of culture! Woo!