If we want to get upset about the Cardinals refusing to trade away prospects for known talent, the Marcell Ozuna trade that saw them give away Sandy Alcantara is how you play devil's advocate for the risk involved in these kinds of deals.
Alcantara was the Cardinals' number six prospect in 2017, behind fellow pitching prospects Alex Reyes and Luke Weaver. Despite making his MLB debut that season, the club decided to package him and number 24 prospect Zac Gallen (more on him later) in a deal for Giancarlo Stanton, who refused to waive his no-trade clause. They then followed that up with a deal for Marcell Ozuna, who was coming off an MVP-caliber season.
For as awful of a trade as this turned out to be, most in baseball, including Cardinals fans, loved the deal at the time, as they were able to acquire a big bat for their lineup while holding onto prospects like Reyes, Weaver, Jack Flaherty, Harrison Bader, Carson Kelly, and more. But based on what we know now, the Cardinals gave away one of the most valuable arms in baseball that would have been their ace for 2023 and years to come.
In 2022, Alcantara won the NL Cy Young after going 14-9 with a 2.28 ERA while leading all of baseball in innings pitched with 228.2. Alcantara is one of the few true workhorse aces left in today's game, making it even more painful to see him finding so much success in Miami.
To be fair, most believed Alex Reyes to be that guy, not Alcantara, so it's not like the Cardinals gave away a guy that everyone knew was going to be a stud. But still, having the 27-year-old in this rotation would completely change how the league views the Cardinals in 2023. Now, the same can be said about the other pitching prospect that got dealt in that deal