The reason why high school coaching is declining is because of parents. I'm a supporter of travel baseball but it has created a culture that just because you pay for it then it entitles you to playing time everywhere. While that is not always the case for everyone it has created the situation where coaches are fired for not playing a kid with squeaky wheel parents. This is also created by weak administrators. Parents don't like what high school has become but the loud minority has only themselves to thank for it.
High School coaching is declining because The Game is passing a lot of those guys by. Swing down to contact, the short quick guy plays middle infield, the fast guys hit at the top of the order (regardless of OBP), it is totally fine for a kid to go play Short or 3rd after pitching, the value of bunting, anybody can play first base, etc etc I could go on & on.... So many falsehoods that have been proven to be mostly a thing of the past.
"Tobacco spitters", that is a good term for them, 2020Dad! Parents & kids have gotten wise.
Now look, I understand that in some parts of the country the high school Baseball is wonderful (consider yourself lucky!) and there are some great high school coaches out there, but from what I can tell a huge majority of high school Baseball coaches out there are glorified Phy Ed teachers/babysitters.
And don't get me started on the idiocy that goes on when a Baseball coach without a degree in exercise physiology supervises weight training. Or the lack of knowledge when it comes to arm care for pitchers. If my kid was a top flight pitcher with D1 or pro potential I would keep him far away from 99.9% of high school programs in America. (Edit, OK maybe 98%)
High School coaches don't like Travel Ball because it has taken their control away. They no longer get to manipulate families with threats of never making Varsity if a kid doesn't play in the high school summer Legion program. They no longer hold all the cards when it comes to a kid's recruitment or lack thereof.
Yes, parents can be part of the problem for high school Baseball, but imho they are but a tip if the iceberg.
Now, I'm not the type of parent that would try to get a coach fired or try to change a program. But I do recognize that there are other options.