>>2592135great thread, op.
the way a wetsuit works is by holding a thin layer of water in between the suit and your body. if you're not in the ocean then that later of water will be your own sweat. the thicker the wetsuit the less exchange there is between ocean water and body temp water, sealing you in essentially. ask any surfer and they'll tell you at some point they wore a wetsuit that was TOO thick and they got hot from just your normal swimming around. (you'll see them unzip the top part and wear just the legs on hot days.). the thicker the suit the less mobility you have. finally, wetsuits are heavy, they don't have to be lightweight because everything is lightweight under water. not breathable, low mobility, heavy: 3 reasons why a wetsuit is not a good idea for backpacking. hope this was informative op. sincerely, a surfer.