ROB doesn't have the
disjointedness to deal with MK's transcendent priority. It's not like you can shield ROB's FTilt and crap on reaction either, OS. But why entertain A2ZOMG at all?
Everyone knows he's simply a troll/moron/both. And
everyone is better in BBrawl, except MK/Snake.
Past very low percents where DThrow-UAir is virtually guaranteed, DThrow doesn't even lead into anything but a limited chance to juggle. Most characters you can still potentially mindgame into continuing the juggle, at any percent, but MK can Tornado to beat UAir if he sees ROB leave the ground. A well-spaced DAir can also beat it... which just leads MK toward his usual air camping.
An easier pivot grab option would be nice anyway, mostly because FSmash just isn't fast enough to pull on reaction. I dunno about you guys but I basically have to just sit there, wait for MK to run out of jumps, and then wait specifically for the Tornado to FSmash him out of it. Otherwise, it just comes out too slow. You can't jump at MK ever, he can Tornado on reaction and it'll
usually beat any aerial ROB uses. (Both laser and full-charge Gyro win, though!) But then what if he doesn't Tornado? Maybe I can punish his landing lag with a projectile but that's about it. He can mix up the timing on his Tornado and if he does it low to the ground, while I'm pressing B to shoot something where he'd otherwise land, I still get punished. Moving away just gives away stage control and FSmash isn't fast enough on reaction if you move toward him, relegating you to simply hope you don't get shieldpoked and can punish OoS.
i.e. Tornado's a *****. Luckily, it doesn't also kill except in extraordinary circumstances.