I do the official Game Changer for the team. Also I love to watch my kid play. I just don't like my kid getting yelled at when others can do worse and get nothing. I'm sorry if that's dumb of me to want to protect my kid and want fair treatment for all players.
Nothing you described rises to the level of needing protection. You described a single instance of "unfair" treatment, and I can (and did) name a bunch of ways it may not have even been unfair. Or maybe it was. Maybe the coach unevenly applied "discipline" (important to note she suffered no real consequences for her mistake) that one time. Does this happen routinely? You never said.
Do you want fair treatment or do you want exactly equal treatment? Because you've described treatment that's not equal, but I can't say it isn't fair (or correct).
If I have a player who has 5 years experience and a player who is playing for the first time, should a coach address them making the same mistake in the same exact way? Because you seem to think so (and you'd be wrong).
Or what about this: A coach has two players she knows pretty well. They have different personalities. One of them sometimes gets a little lazy and needs the proverbial kick in the backside to get it together. The other will absolutely shut down if she gets yelled at, especially with others around. Should the coach address a mistake from those two players in the same way?
Also when your kid is afraid to talk to the coach about concerns they have - what are they supposed to do? He doesn't exactly give off the vibe that he is someone willing to listen to questions. When he takes her out and subs someone else for her - she said he tells the other player but not her. So she'll go out to her position and then be called back in because he never told her. I've told her to just ask every inning if she's still playing/hitting until maybe he gets it and realizes he should communicate stuff like that with her. She won't because he looks at her like she's an idiot since she should always just know what he is thinking.
I know everyone says HS ball is just something you have to deal with and I really want her to be able to play with her friends. But it hurts me to hear her say that she was really excited for this year because she thought the coach had finally started to respect her some but then stuff like this happens and makes it not fun anymore.
NOW you're hitting on a real issue! It's too bad if the coach is not approachable and doesn't communicate well. I wouldn't call it a red flag, exactly, but it is a failure of that coach. He seems to be missing a key quality needed to be a good coach. That said, I have definitely forgotten to tell the person coming out of the game before. If he does it all the time, or if he specifically does it with your DD only, then maybe there's an issue. Did this happen once? Is it just his way to not tell the person coming out?
I'm looking at everything you've said here, and if getting yelled at one time when she did something wrong and the coach forgetting to tell her she was coming out one time is all it takes for your DD to not have fun anymore, that doesn't say a lot about the coach.
I read all the Terrible Coach threads here. I see some pretty bad, dumb stuff from these coaches. But in this case, you have a kid who gets plenty of playing time who just might not be quite as close to the coach as some other players (but it doesn't actually affect her standing on the team).
Just curious: Does your DD also play on a high level travel team?