I'm all for building apps to solve problems, but I would really encourage folks to ask people politely to do what you want them to do, rather than having an app do it for you.
You can just ask people for things! And you will become a better person for it.
Asking people publicly tends to challenge their ego and bring up defensiveness. It would fail a lot more than subtle manipulation like this, and instead bring additional confrontation.
Nobody is suggesting he deserved to be punched or that there are some unreasonable violent people around. Yeah, he could have died. But saying he actually did is a lie deployed to get attention, I can't stand that.
You can just ask people for things! And you will become a better person for it.