Jake Bauers is actually the counter example to your argument. Former Top 100 prospect, Milwaukee is his sixth organization, and he has a career WAR of 0.3 in nearly 700 games. (Also an example why using metrics as a measurement of player quality can be misleading).
I do not understand the relevance to your argument that Brewers hitters 28 and under have a certain WAR since 2023. The Brewers don’t sign veteran free agents, so of course their roster is going to be younger. Ohtani, Betts and Freeman are all over 30 have close to 69 WAR combined since 2023 not counting the rest of the Dodgers.
I don’t believe there is an objective way to conclude the Brewers are better than most teams at identifying and developing amateur talent. With the price of free agent talent today, developing their own talent is more essential for them to remain competitive than it is for the Dodgers, Padres, Mets, Cubs, Braves, etc. Their results may be more visible because they’re not going to fill holes with veterans on multi year deals.
Circling back to Top 100 prospect/top prospect ranking lists. Take a look at some from 7-10 years ago. There’s always a few players usually near the top who became key contributors in the majors, also there will be a significant chunk of the players on any given list who never did a thing in the major leagues, and the majority of players on those lists are guys like Jake Bauers. Toolsy players who never became difference makers and bounced around the league as useful players. Which is to say I’m not suggesting an “F them picks” mentality like the NFL’s 49ers, but rather the notion of treating minor league players as untouchable commodities simply because their name appeared somewhere on a prospect list, is misguided.