Norm, I am new here, so I certainly don't want to stir the waters. I was just giving my opinion after watching him compete against these guys down here for a number of years.
IMO, just because a player doesn't appear to be athletic on a video or even exhibit athleticism in a very structured environment in person, doesn't mean he's not athletic. System play requires different things from different players. I can only report what I've seen for myself, and then draw conclusions from reading where coach Miles has said in statements to the media, that he also thinks he's long and athletic.
FWIW, here's what Rivals in Texas, who's seen these boys play more than me for sure, have on his scouting report:
"NATHAN is a very athletic wing with the ability to impact a game in many ways. He slashes to the rim, finishes strong on the break, has good bounce in the paint and can create his own shot off the dribble. He has a smooth stroke, can hit the open 3 point shot and has a nice pull-up jumper. He can go to the boards, can start the break, has good speed in the open floor and handles it well. He can guard multiple positions as he moves his feet well, has long arms and a strong body."
As for high-flying athlete, yeah, he's not jumping over cars or catching oops with one hand, 2 feet above the rim, as he comes swooping in on a fast break. I'll agree with that for sure