In my experience, the higher the level, the less ranting and raving I see from the coaches. Of course, there are exceptions to that, but as a whole, that's what I've found.
To pile on, the rantings of sub-varsity and lower-level high school coaches, in particular, are far, far worse than those at the FBS level, to which I can attest. I have not worked, and will never work, in the NFL, but I suspect the same is true for the NFL, i.e., their rantings are less often, and are far more fact and truth-based than any other level. There is a reason for that: The NFL officiating office works far, far more closely with the teams than at any other level. The teams know the rules better, and they also know the officials on a slightly more personal basis, so accusations of bias are fewer and further between.
At the FBS level, there is a respectable level of coordination between the schools and the officiating staffs, and the coaches at that level are, again, far more knowledgeable of rules, mechanics, and procedures than high school. Yes, they will rant, but they know there are consequences if/when they get out of line. They have much more accountability. So, they tend to not get out of control.
Sadly, at the high school level, there is not much coordination between teams and officials, outside of scrimmages and games, to help either/both to get better. Try to organize a voluntary meeting with coaches to discuss rules/mechanics/procedures, and you get a small percentage that will take advantage and participate (like 17 schools out of 75). Obviously, there is virtually zero coordination with sub-varsity coaches/teams. Those guys only know of rumors and hearsay about the rules. They definitely get out of control, at times.
But, that's the way it has been throughout my 44 season career. I don't see anything changing. We just do the best we can, honor the game and our fellow officials, and keep moving forward.
Robert