Giannis and Thon both came into the draft as skinny, raw prospects, without any high level basketball experience. However, in Giannis' rookie year, he played roughly 1900 minutes, whereas in Thon's first two year he accumulated 1800 minutes.
Here are the per 36 stats after Thon and Giannis' their first 1800-1900 minutes, per basketball reference.
Thon: 12.2 PTS, 4.9 PF, 1.1 TOV, 1.6 BLK, 0.9 STL, 1.4 AST, 7.1 REB
Giannis: 10.0 PTS, 3.3 PF, 2.2 TOV, 1.2 BLK, 1.1 STL, 2.8 AST, 6.4 REB
Here are the per 36 stats for the ensuing year (2014-15 for Giannis, 2018-19 for Thon):
Thon: 14.4 PTS, 4.8 PF, 0.8 TOV, 1.6 BLK, 0.9 STL, 1.6 AST, 8.4 REB.
Giannis: 14.6 PTS, 3.6 PF, 2.5 TOV, 1.2 BLK, 1.0 STL, 2.9 AST, 7.7 REB.
Kevin Garnett, who gave both Giannis and Thon personal coaching attention, said that Thon had the raw talent to win MVP. I'm not saying Maker will 100% win the MVP. I'm saying that there is no reason to believe that he can't be a very good player.