I have said somewhere between 4th OF and average regular. That is the consensus opinion. You do realize that above average regulars tear up the minors with age appropriate performances in the 800-900 OPS range all the time. At age 21 Nick Williams put up an 845 OPS (876 in Reading). Moniak is better defensively, but worse offensively and at no point did I ever consider Williams to be a likely above average regular either.
It seems you are more willing to criticize my comments, than to actually look at comparable prospects and the industry consensus. Are you expecting Moniak to be a top 100 prospect this offseason? Is there a reason anybody should expect that? When I say he is 8-12 I am probably saying he is top 200-300. Still a good prospect. But not top 100.
Example - Here is the Fangraphs scouting report from him before 2019: "There's still a chance for a solid regular here, with fringe-to-average offense and defense in center field, and his age vs. level masks his ability a bit, but we'd like to see what changes are made in 2019 before totally buying in."
He might have improved a bit since then, but his #11 current ranking in the organization is probably not going to change more than a few places.