Why did they add Drew Rom to the 40-man?
Of the ten players the Cardinals received at the deadline, only two made the 40-man roster. The first was John King who is already with the major league club. The only other is Drew Rom. It's a bit confusing on the surface. Kloffenstein, Roby, and Robberse have stolen the headlines and are arguably much more exciting players, yet Rom finds himself on the 40-man roster.
This is why Rom has the best chance to debut in 2023 of any of the prospects the Cardinals got at the deadline. As previously stated, Rom doesn't have the highest ceiling of these prospects. He's actually struggled quite a bit this year. However, he does have the most experience at the AAA level. None of the other pitchers have spent significant time at the minors' highest level. Most have limited experience in AA. Thus, even though a pitcher like Roby (who is injured right now) or Kloffenstein may have a higher ceiling, Rom will get the first shot.