Aero bars just suck, if your handling abilities are ok probably is not a problem but like 90% of the suckers that use aero bars, aero bikes and are casual riders or week end warriors w/o experience in the real world of racing, so they will suck at handling and at some point they will have an accident or will be really close to have one. Seen too many since the bars came up like 30 years ago. Besides, for going 20 mph if the guy is trained or fit, the rider can do those speeds in a bike from 1945 with paniers and stuff. Since many guys ride in straight paths is not a big issue until something cross the road (kids, animals, bad calculations, etc) and they end in a ditch at the side of the road with a broken bone or something. Two weeks ago i saw a lady between 45 and 55 being taken off a ditch by the paramedics and her bike had aerobars... as i said before, seen too many already. Saw the problem with the handling 30 years ago and looks like people just like to follow the trends, good for cycling business, medical suppliers and hospitals.
Not saying I ride fast ok? my riding really sucks since retirement but pretty much thats how i see the issue with the famous and useless aerobars.