Fine. Others are—including some professional evaluators who've seen him. And they're not wrong to be.
Personally, I'm not going doom-&-gloom with him—his combination of stuff is impressive, and age is on his side—but I'm also not going to just assume he figures out his command/control issues simply because he's young—plenty of young, talented guys never do. I certainly hope he does, though, because—if not—he's at best a middle-reliever, which is not a tremendous return on the #3 pick (although anytime a pick sticks in the majors, in any role, it's a success).
Are you not basically just saying, 'This very young prospect needs to develop, or he won't end up being very good?'
That seems like it applies to all very young prospects, or at least 99.9% of them.
Sure, if he doesn't develop any further at all, he'll be at best a middle reliever, which is not good investment on the #3 pick. I'm not sure how that's breaking news.
Here are the other guys in the top 10 that year:
Mickey Moniak - sucks and has lost all value as a prospect
Nick Senzel - hit very well the last 2 years; really, really good prospect
Riley Pint - has sucked way harder than Anderson; now dealing with forearm tightness and appears likely headed for TJ
Corey Ray - sucked last year, not looking great so far this year; very, very meh as a college draft pick, definitely lower stock than Anderson
AJ Puk - pitched very well last year, now unfortunately headed for TJ
Braxton Garrett - looked ok to start last year, then unfortunately had TJ
Cal Quantrill - pitched fairly well the last couple years as a college arm, but lower K/9, likely never going to be anything resembling a TOR starter
Matt Manning - has struggled with BB even more than Anderson, still in A-ball
Zack Collins - has played well so far, but clearly behind Anderson in prospect rankings
Let's keep going with some guys Braves fans specifically wanted that were taken 11 and 12:
Kyle Lewis - played ok last year coming back from injury, yet to play this year
Jason Groome - struggled with BB more than Anderson last year, still on the DL
Obviously you can't do anything about the injuries. Those are bad luck, and Anderson still could deal with his own issues at some point. But please point to me the guy who was still there when we picked 3rd and tell me the guy who obviously has been better than Anderson and who we would rather have at this point.