A googolplex people being dust speckled every second of their life without further ill effect

I don't think this is directly comparable, because the disutility of additional dust specking to one person in a short period of time probably grows faster than linearly - if I have to blink every second for an hour, I'll probably get extremely frustrated on top of the slight discomfort of the specks themselves. I would say that one person getting specked every second of their life is significantly worse than a couple billion people getting specked once.