I agree with IEBSBL - Even at a very deep school - My son's HS team won the State Championship and had something like 14 DI players in the program at the time but there was no real competition. The few places it existed was at the 3rd outfield spot, 1B and the 3rd/4th pitcher.
In a 10 team district this place could have won or done no worse than 2nd in the with the team it had on the bench. The JV team could have finished 3rd with the varsity pitching. Other than pressing a few buttons occasionally - the same 8 started almost every game.
It is easy to overthink this stuff. A couple of kids along the way banged heads with the coach - they lost because he didn't need them. I do believe the coach generally had the right team out there.
If there is one thing I learned watching HS baseball for 7 years it is this - coaches want to win. They really do and they are putting the best team out there to give them that chance.
I was always amused by the noise on the sidelines - conspiracy theories about cooking food at the concession, raking the field, or all the other ways you can apparently "brownnose" a coach. I would privately laugh, write the checks that were required and watch the games.
When finally asked what I thought was going on to determine the line up - I said - "Coach is putting what he believes is the best team he's got on the field". What I got back was priceless - "Do you really think so?" and my response to that "Why would he do anything else?" After that - blessed silence as I watched the game.