I don't think that's true. Certainly you can't just concede games like you theoretically can in the tournaments, but coaches are balancing every game against developing players for conference games and figuring out roles. If you're going to discount tournament games, should you discount midweek games? At best your 4th starter is playing midweek games for power conference teams. Probably worse than 4th starter because you probably have one or more bullpen options that could start are kept in the bullpen because they are better and you want them for the weekend. Do lower conference teams ever get the best shot from power conference teams?
If you're splitting hairs to the point of actually comparing individual wins and losses between two teams, sure consider whether a big win or bad loss was early in the year, or whether they picked up an easy win against a national seed coasting in their conference tourney, or if they picked up a good win playing against a team dealing with several important players on the other team were temporarily out with an injury, or picked up a bad loss when several players on the team in question were temporarily out with an injury, but I don't think it's legitimate to just discount tourney games as a rule and not others unless there is a time constraint.
What you’re missing is that “carving out roles” is a byproduct of the coaches not yet knowing who all their best players are in specific situations, in the real games. Coaches never play worse players intentionally over better players unless they are blatantly conceding a loss (example - not wanting to burn good pitchers after getting down in a huge deficit), or they are playing in a game where they know before the first pitch is thrown that it really doesn’t matter if they win or lose - like a guaranteed national seed playing in a conference tourney game. And the coaches on the other side in any early season game are doing the same thing, and for the same reasons. So, it’s a wash.
The midweek game argument? That’s also a wash. You’re only arguing one side of it. Of course lower conference teams don’t get the best shot from the blue bloods in the midweek. But the blue bloods don’t get the best shot from the lower conference teams, either. Those lower conference teams also have weekend series, against conference foes, that require them to save pitching. And those games are far more important for them to win, no matter how much exposure they would get from being giant killers for a day.
Coaches playing marginal players early in the year, and it not working out, does not mean at all that they aren’t prioritizing winning. They still very much believe that the player in question is one of a handful in a particular role for which there was not enough separation in practice to determine who was best. So, games are then used to gather more data and carve out the long term plan. Same is true in any other sport.
And as far as if it’s legitimate to discount tourney games? I’m not saying that it is. I’m just saying that it DOES happen, right or wrong.
