I guess my question is why have you written off the prospects the Braves have at the lowest levels and written off all the players the Braves will draft and sign over the next few years?
Swanson is controlled through 2023.
Albies through 2024.
Acuana through 2024 or 2025.
Any pitcher promoted next season likely through 2025.
Any position player promoted controlled later.
To say the Braves don't have waves of talent coming is to write off the majority of the Braves system below Florida and to write off all the players they will draft and sign internationally over the next four or five years. They aren't going to stop accumulating players from here.
I'm not saying it is definitely going to work out. That's an open question. But to say they definitely will not be able to keep it going is based on information no one has.
I haven't written those guys off. Those guys likely will be on the leading or second wave of talent the Braves have, establishing the winning, not setting up to continue it.
I am pretty much writing off the first wave (I consider Acuna as part of the second wave). The first wave was Folty, Newcomb, Wisler, Blair, Ruiz and Swanson and Albies. Out of that wave, it appears to me that the only ones likely to
see 2020 as a Brave is Swanson and Albies and neither have shown a likelihood of stardom (which is ok for them since not every player can or will be a star, but the first wave should have produced at least one to replace the aging stardom of Freeman and/or Inciarte).
Freeman is a borderline superstar (likely a superstar this year without injury) but will be 30 in 2020. Inciarte a legit star will be 29. That means both will be in the beginning years of their decline phase as baseball players assuming they baseball age as normal. Will Freeman still be a borderline/true superstar? Unlikely. Even if he's "still good" he's not prime good anymore simply because that's not how it works. Same for Inciarte. So, your best players of today are likely fading players tomorrow of different shades at best with a worst being loss due to injury or other factors. They also will be approaching their FA times where if the Braves are smart, they will let them go elsewhere which means they have to be replaced. If they aren't smart then they will be extended again which means not only that they can't be replaced but limits the payroll space to address other areas even in the face of lost production.
In 2020 Teheran is gone, Folty is gone, Newcomb is probably in the pen if not gone, no one knows who Wisler and Blair even were. The pitching is very reliant on the second wave of Gohara, Allard, Soroka, Wright, Fried, Touki. Right now, the best guy of that group is a fat import in Gohara. Allard and Soroka both look like they could make it but both probably won't. Wright may come on but so far looks limited on stuff required for a ML #1 or #2 (we'll see). Fried and Touki are wildcards but 2017 didn't really help Fried and Touki remains a mystery with poor results besides improved numbers. Let's say 2 of the group become good useful ML starters by 2020...say a #2 and a #3 with one of the others being good enough to handle occasional #5 duty.
Then you have Acuna as part of the second wave. Maybe he becomes a superstar and helps carry the Braves to the wave of competition in 2020. But, in 2021 he looses and aging Freeman and in 2022 he looses an aging and less effective Inciarte (likely no longer has the same value because CF becomes harder to play for him).
So, you made it to competitive level with the second wave mostly having to replace an ineffective 1st wave. You have an expensive and declining Freeman, a relatively inexpensive but declining skills Inciarte (his value is as a CF and LO hitter; if he can't play those as well he's not very valuable) You have Albies, Swanson and Acuna either in FA or getting close so, assuming all are effective, then their cost will offset the removal of the Freeman and Inciarte obligations.
So now you are reliant on the Braves third wave of Maitan, Waters, the other International signees etc. to remain competitive. That may happen. But, you have to expect that to get to competition in the first place in 2019/2020 and stay there for a year or two some of the young talent will be traded to fill holes.
But what about the draft and International signings between now and then? Assuming the team gets incrementally better between now and then as designed, then the likelihood of impact talent decreases significantly and becomes more a function of luck.
Could everything turn up roses for the Braves even given their past and current mistakes? Of course. But, IMO, it will rely much more on luck than design.