I think as a number of posts have picked up on wearing clothing that isn't going to burn you badly could be just as relevant to a post crash fire as an in flight one. Obviously we do not know in this case but it could buy valuable time for example if you were trapped in a burning aircraft after a crash.
Does not necessarily mean I will start wearing nomex all the time but I might pay more attention to what my passengers are wearing for example. I almost always were cotton anyway when flying or otherwise since I do not like synthetic fabrics. I always take my hi vis (if I have bothered to put it on in the first place!) off when getting in the cockpit as well.
Nice to see a reasoned debate on this subject.