Prior to learning to arc weld, I always thought the primary danger of looking at the arc without protection was UV exposure. However, it turns out that IR exposure is also problematic. See, e.g., https://en.wikipedia.org/wiki/Glassblower%27s_cataract
Not to downplay it, but cataracts are probably the easiest operational procedure on the human body. At least in the rich world.
Most people will have to deal with that at one point in their life.
Source: Myself; I got both of my eyes fixed last year. While I can appreciate the horror of your eyes cut up, the actual operation is really minimally invasive.
Mind you, I'm not arguing that excessive IR - or UV exposure is generally a good idea.