Not snagging a top pitcher
The need was very clear for the Cardinals: get a starter who could slot in at the top of the rotation for both this year and years to come. Sounds pretty easy, right? Not so much. A player such as Cease or Gilbert, both aces on their teams with years of control left, would have cost the Cardinals a lot, particularly players they are fond of (Lars Nootbaar, Nolan Gorman, or even Jordan Walker).
Despite the price, the need for an ace or ace-type pitcher was very high for the Cardinals. The team should have been more willing to part with its controllable pieces for a very clear need: pitching. The prospects the Cardinals did get should help the team plenty. They can play in the minors now, allowing Zach Thompson and Matthew Liberatore to see time in the majors, and they could continue to develop and become good starting pitchers in the near future for the team.
However, the Cardinals don't need more mid-rotation pitchers; they have plenty of those already. What the team did need was a top-tier pitcher. Not getting one of these pitchers at this deadline is one way in which the front office fell short this year. Hopefully, a trade for a starting pitcher is in the plans for the offseason. Otherwise, the owner will have to open his checkbook, or the fanbase will be let down once again.