1. Jordan Montgomery, Jack Flaherty, and Jordan Hicks will all be dealt at the deadline, yielding great assets in return.
I've seen people speculate that the Cardinals could look to extend any of these three, or just give them a qualifying offer in the offseason to get draft pick compensation. I would bet that we see all three traded away before the deadline.
Why? Well first, John Mozeliak himself said they are going to trade people and left very little doubt that some of those people will be their impending free agents. He told me back in early June that they could look to capitalize on the value of their impending free agents if things did not turn around, so they've been preparing for this scenario for a while now. Second, he has indicated that they aren't concerned with getting draft pick compensation.
The Cardinals could go out and pursue a reunion with any of those three in free agency this offseason, but keeping them on the roster gives them little to no edge on their competition this winter when it comes to signing them. All three are going to look for the best possible contract they can get, and if St. Louis trades them away and then outbids the rest of the market, I'm going to guess that they will be willing to come back.
Third, which I think is the most important reason, is that all three are going to have a lot more value on the trade market than you would expect. Take a moment to go on FanGraphs RosterResource and sift through the rotations of every contender. All of them need starting pitching, and both Montgomery and Flaherty would be major upgrades for them. Hicks will also be coveted by many of those contenders.
I can see both Montgomery and Hicks netting the Cardinals a top-100 prospect in baseball in separate deals, or very intriguing assets for the future of their club or to use in trades later down the line. Flaherty should also net them a good return, as the pitching market is so thin right now that all three arms will be some of the best available.
Other GMs, like Kim Ng of the Miami Marlins, have already stated how much of a seller's market this is. Players are going to come at a premium, which will work greatly in the Cardinals' favor. This should really help jump-start a retool for the 2024 season.