Meaningless probably isn't the best word to use and I know I've used it before. There is a lot of middle ground between meaningless and meaningful and the conference tournament falls somewhere in there. Winning is always better than losing and I don't think anyone here is saying to purposely throw games. But in a sport like baseball with so many moving parts/players, there is a fine line you have to walk at this point in the season.
Conference tournaments are unpredictable, with varying motivation factors among teams. Some need to win it, some are indifferent, some are ready to go home. Some pitchers need to throw, some need rest, some need film for the portal opening next week. Some teams have guys who could use a few days of extra rest while some need to reps for players who may have recently entered the starting lineup. We had Jared Thomas and Peyton Powell fighting through pretty significant back injuries last year at this time, and the full week of rest did wonders for their regional/super-regional performance.
Similar to the conference tournament in basketball, there is very little evidence that winning or losing foreshadows what is to come, assuming you already have a postseason bid locked up. If we can accept that while still hoping for wins, it makes this week less stressful as the buildup for the real tournament starts.