Because that's what happened. There was other stuff surrounding it, but those kids were absolutely being completely awful anyway.
But conservative media spun it as completely misunderstanding, made some lawsuits, pointed out the other facts, and that let off scott free… even though they were still being completely awful. That there were others ALSO being terrible doesn't completely negate that fact or absolve them of how they were acting.
To make a completely non political example.
You order a pizza. It's a delicious high quality 4 toppings, super good pizza.You eat the entire thing, and you declare it is the most disgusting thing you have ever had, and you say so. For some reason, the media reports on this. You hate pizza! The facts are in, you're on camera hating pizza, you said so, its absolutely clear!
But it turns out, that somewhere in the process, your father had drizzled chocolate sauce all over it, so that you could have a taste adventure. The pizza was actually completely ruined, and disgusting. But you ate it anyway because you don't want the good pizza to go to waste despite being awful.
So now the story is clear, it was actually your father that was terrible, the media got the story all wrong, you're in the clear, you like pizza after all! You're an innocent in all of this!
But then it turns out that the toppings you ordered on your pizza included walnuts, shrimp heads, bologna, and peanut butter, with mayonnaise for sauce. It was a horrible thing even before your father ruined it.
You actually ARE still are a horrible person that hates pizza, that did something bad, even if there were outside circumstances that seemed like they could have made you look innocent. You still did stuff outside of that influence that was awful.
But the media only focuses on your father adding chocolate sauce, so you're forgiven anyway and everyone eventually forgets that you had a walnut and shrimp head pizza with mayonnaise and peanut butter.
That said, no one should send death threats over such things.
Are you suggesting someone standing still not saying a word or lifting a finger in front of someone distressing him is an awful thing to do? I ask this sincerely, please point to me said evidence of Sandmann acting awful in front of Nathan Philips and deserving of your accusations so that i may see what your point stands on.