My real question here would be: "Would that gentleman have referred to you as 「あなた」 if you were a Japanese girl of your age?"
If that is how he usually refers to others, then that is just his speech style. Whether that is common or not is not his concern. In all of my life as a Japanese-speaker living in Japan since birth, I honestly have yet to encounter a person who does that. But who knows? Your friend may be that very rare Japanese-speaker.
Another thing I would like to mention is the fact that quite a few Japanese people speak a "different" kind of Japanese when they speak to non-Japanese people. This is probably not openly mentioned often but they do that. Some of you may have noticed it as well.
The frequent use of pronouns is one big feature of this "different" kind of Japanese that I speak of. It is also heard/seen in Japanese dubbing and subtitles of non-Japanese films, dramas, animation, etc. Though to a lesser extent, pronouns are more often used in fiction (than in real life) that is originally in Japanese as well.
So, it is difficult to discuss what was intended by the short sentence 「あなたはとても、すごいです。」 taken out of the context. I personally do not really feel that it conveys distance but that is just a feeling. He may have used 「あなた」 here because he had already used your name a few times immediately before this.
(To be completely honest, the sentence 「あなたはとても、すごいです。」 does not flow well. Why the comma? It looks like something a begnning J-learner would say. It looks like it took one 3 minutes to form that sentence.)