If I could convince Aubrey de Grey to cut off his beard it would increase everyones expected longevity more than any other accomplishment I'm capable of.
I think his look (if his Wikipedia picture and the tiny images from a Google search) is probably not particularly harmful. It's well-positioned to signal Dignified Hippy, which is a group that tends to be skeptical of the general anti-deathist position, or for a general Respectable Elder, which is not wonderful but pretty decent for appealing to institutional-investor-type groups. I'm not familiar enough with his particular relevance to know whether that balance could be improved for what he actually does.
Another month, another rationality quotes thread. The rules are: