The astute are well aware that photos only require a fraction of a second to be snapped. If such people were to be exposed for an hour or more, they'd all likely be dead or near so from hypothermia, as with the victims of the Titanic. You can do short moves bare handed, but for a length of time, you do risk frostbite or similar when climbing a long extended pitch. With wind chill and low temperatures you will freeze tissue, sometimes immediately. I used to go through Truckee when it was sub zero or close, and pouring water on my windshield to clean it, it'd freeze right away. Faster than I could squeegee it.
Keeping your core temperature hot helps, there is circulation. Warm blood does get to your hands, why you keep your head and neck covered. Physiology dictates that 90% of one's heat loss is via those areas, so If you feel cold, they do say to put on a warm cap! Fingers are adapted to touching, so are sensitive by nature. I guess it is possible to desensivitize them, but not recommended.
All in all, if you must climb during freezing conditions, do as you can. Some short moves can be done sans gloves, but to constantly put them on and take them off, impedes the flow of climbing. Given that some enviro club can happily declare themselves winter 5th class climbers by doing a 10' hoist at Berkeley's Indian Rock, say, in December (usually about 50-60 degrees in the afternoon), but a High Sierra peak by a long sustained route in winter is far, far, far different.