A “she-bear bereaved” (see also 18:14; 28:15; 30:21) is the best translation of this passage and this bereavement is best understood as relating being robbed of her bear cubs. While running into the average bear might not normally be considered a major problem, meeting a mother bear “robbed of her cubs” would be scary.
But this verse says running into her is still not as precarious as it would be running into a “fool in his folly” – doing his stupid fool stuff. No one would have to tell us twice to avoid that bear. Yet, many of us somehow think it is okay to hang out with that fool because it won’t be that bad.
Bad move. You can’t talk any more sense to the fool than you can with the bear! Better get away, because the carnage will be even worse than running into that bear.