Well, lets just look at his MLB numbers at age 20 (and, yes, I realize that is a small sample). In slightly over 1/3 of a season, Ozzie put up a WAR of 1.4. Projecting that over a full season results in a 4 WAR season at age 20. Do we agree that virtually every non-steroid fueled player has a performance curve that peaks around age 27? If so, and if his WAR last year was accurate, is it unreasonable to see that he will peak in the 6+ WAR range for his 26-29 seasons? I don't think it is.
Even if his 1/3 season was a little flukish, and his true ability is reflected in a 2.5-3 WAR season in 2018. How many players in MLB history have posted a 3 WAR season at age 21 and haven't, barring injury, peaked in the 6 WAR range at ages 26-29?
So are we to assume that his power peaks but his defense and speed stay constant through his late 20's as well instead of declining which is what usually happens to players as they get older?