Yup, nothing wrong with safety gear and I fully support bringing it (falls into what I wrote above).... but some people seem to think they are more protected with it and can gain a false sense of security which can get them into MORE danger.... Kinda like 4x4 drivers in the winter..... all-ways the ones in the ditch, lol.
A life vest won't protect you from the cold, but will keep you floating. Unless you can get your self out and warm you can still be in danger.... Better hope to have a plan after you float down the river.... It is winter
I fish spots that have less people so self rescue is my only option a lot of the times and I fully understand the effects of cold water.... not everyone does though...
Be safe!