You've left the geanie so much room for interpretation, for example:
Take 30 seconds to do the task of giving all blind people eyesight.
You didn't say when these 30 seconds happen. Could be all at once now, but could also be everyone at their last 30 seconds to live.
"Eyesight" could mean that there are eyes sighting the blind one. So there's just someone around that looks at the blind person.
You didn't say that the people have to be alive. So now, they become zombies for 30 seconds. This means somewhere where there's a living human next to a dead blind human, the living one gets bitten, and the zombie disease can spread.
Not to mention it doesn’t say only 30 seconds so if all blind peoples eyesight is restored for at least 30 seconds then the genie could just restore it forever.
Each blind person gets horrifying deep sea fish eyesight or the eyesight of someone committing murder and now they all are thought to be hallucinating.
What are the three wishes that would cause untold amounts of mental damage to marginalised people without death or permanent changes to their daily life?
Jokes on you, I give all blind people 30 seconds of sight once in their life at the single most useful moment. Blind people worldwide regain their sight just in time to avoid accidents, to see their loved ones right before they die, or to save their children from danger.
Except they might not understand what they see. As a kid I asked a legally blind buddy what he would do if he suddenly could see clearly and he said “probably freak out. Im used to my vision as it is now I don’t know how to do anything as a ‘normal person’”.