The alternative - that it might be fake - isn't any better, is it? Because in that case, what, they're picking on and making fun of people with similar issues?
That Greatest Freakout Ever did NOT look fake and he seems helpless against the sounds he's making as he screams. He's choking...this is SO MUCH like my Classic/Kanner boy...so much...my son doesn't get this entirely out of control but all the things he's saying...he wants to get out, he hates his life, and how he paces helplessly and frantically toward the door, stops short, runs back to the bed, throws the covers over...even the way he runs, lurching side to side...threatening to throw things but clearly he doesn't want to, he's that desperate, then he finally does throw the item and kind of jerks back like "NOW I did it" in fear...OMG...this is my son. This brought me to tears.
I clicked on a second video, I don't know why, maybe I'm a glutton for punishment or maybe I was just so shocked & couldn't believe this...and the mother is involved...she isn't saying, "What the hell are you boys doing? Why are you acting so weird?" I don't see much indication that this is fake in light of that, unless the mother is somehow in on it too, and I somehow doubt that. I mean if your son didn't typically act like this and then did, wouldn't you be going, "What...the hell...are you doing? Is this some kind of joke?" or whatever? She doesn't do that, she keeps arguing with the specifics of what he's upset about.
Meanwhile, the father is clearly in the one video and DOESN'T come rushing in to say "What on earth, I hear all this screaming"? That would also seem to indicate that this is a normal thing in the household, I mean if this boy were NT and didn't do these things, and the dad all of a sudden heard hysterical screaming and items being thrown, he wouldn't come running?
If it's real, shame on the brother. If it's not real, shame on the brothers. And mom. And dad. And every other person in these videos who is acting upset but not as if this is totally weird and something their son doesn't actually usually do.