Ok, a couple things. I'm a big noob, no where as good as your Mario. But that just means if I can see a pattern, sure as anything whoever you're fighting is gonna see a pattern.
More often than not, you pull out the cape stall. Don't get me wrong, great tactic against a good majority of the cast. Maybe against ROB too, but with ROB's range, it's not a great tactic. Either cape stall is a habit or muscle memory or something (which would explain why you pull it off so well) but there's a time and a place. In my opinion, not so much against ROB. I'm not saying, "Don't do it". Just not so much.
Your aggressiveness is freakin awesome man. You make Mario look quick. The way I see you drive that Mario, steep, you got the pedal to the floor!
But if you'll let me continue this racing analogy, what do you do when you come up to a turn? Or a couple turns? Tap the brakes a bit man. Slow down a bit. Or else you hit the wall. The way I was reading that match, you kept driving into the wall.
Honestly, I would've done the same. When you were playing your far game, air dancing with fireballs, awesome. But ROB would counter fireballs with spinny top thing and lazer beams. A couple of those would hit, sting you a bit, then you'd charge into his expecting metal arms. I hate to say it, but he baited you. We talk about baiting our opponents with fireballs, sucks, but I think that's what he did to you. If time runs, then time runs. I feel like that dude set the pace for the match.
Idk if that would have helped you win the game, but slowing down, changing the pace of the match on YOUR terms; that makes a difference to you as an overall player. When YOU want to be aggressive, awesome. BE AGGRESSIVE. PUT THAT PRESSURE ON!!
But when YOU realize that's not working, then YOU slow down. Maybe your opponent is only good at reacting and playing defense but sucks with offense. If his offense is predictable, it's a good thing you slowed down in order to read it.
But like I said, I'm a big noob. Maybe there's some mind games or frame data or something that I'm not seeing.
TL;DR
Slow your roll, brother.