I wouldn't exactly say she was robbed either. The Tony voters have the right to choose whoever they want, and they chose Miles.
And since I haven't seen TKAI, I can't really comment on the performance of RAM...or KO, for that matter. Based on the Tonys performance it seemed rather 'meh.' Not exactly any different, vocally, from anything TKAI has done before.
But again, you have to see the WHOLE show, not just snippets, obviously. (Heck, I saw OTTC and thought it was amazing. But I didn't think the Tonys performance of that one played out all that well. They tried to do too much IMO.)
Apparently Sher has taken an old show that is a pretty textbook show when you have the talent behind it (and even KO admitted that the range wasn't that difficult for her), and made it something special. Something different. Somehow.
It's a show that gets revived pretty regularly, and seems to capture the awards every time it does. Kudos to him for doing something "new" with it to make it stand out from all the other times it has made its appearance on Broadway.
As for individual performances though, I still think Lucas captures something pretty special for someone her age. It's in her vocals, in her eyes, in her gestures, in her being when she sings that song and when she performs the role she's in. I always find it impressive when such a young person can do that.
Conversely, you expect someone who is older and experienced to capture the essence of their character. I mean, if they're a good actress and singer. Which Miles is.
I guess that would have been my reasoning for giving the edge to Lucas.