No, we shouldn't, but that kind of question comes with all sorts of caveats. Any decision of this sort, including Vonn's, should come in consultation with appropriate medical experts as well as respect for someone making personal, if potentially short-sighted with respect to bodily damage, choices.
We don't know fully what motivated Vonn to come out of retirement and put herself through this experience. It could be she was finding it boring compared to her prior life of constant training and competition. Maybe she was having a hard time letting that go - we've seen it before (hello, Brett Favre). Frankly, I find it hard to understand anyone choosing to rocket down a mountain on waxed up slats of material because I'm not crazy. But, hey, she took her shot, took home another record-breaking World Cup win, and competed at the highest level at a location she loves. I hope she finds peace and contentment in retirement again.