Before letting your child play under any coach, you have an obligation to perform sufficient due diligence to determine the coach is an “abuser” or “bully” under whatever standard those words mean to you. If you don’t or can’t do that, at least stick around at enough practice until you are satisfied with the situation. If you don’t, you can only blame yourself.
If you are the sort of parent who believes raising your voice ever or dropping an occasional f bomb is inexcusable and merits a lawsuit or punching the coach in the face, there is nothing stopping you from addressing your expectations with the coach at the outset. If they’re a screamer or gravitate toward the more colorful spectrum and are not willing to accommodate you, I’m confident you will agree you are in the wrong place.
Obviously, there are times a parent does their part, but inappropriate verbal conduct still happens. No one has perfect information and coaches are people too; sometimes they go off the deep end. You cannot prevent your child from being exposed to every ill-advised comment in advance but, if you did your due diligence, odds are that it is an isolated incident and nothing to lose sleep over. A few stupid, mean, or “bullying” (if that is the conclusory, factually lacking, but explosive terminology you prefer) comments will never cause anyone permanent neurological damage. If you believe differently, that’s fine with me, but you can’t expect others to share your zero tolerance standard, your significant deviation from societal norms, and some solid research that a strict rainbow and butterfly approach is not the best way to benefit an elite athlete or even raise a child. Also don’t expect people who know a coach not to defend him, especially if you trash them with conclusory words like “bullying” or “abuse” that don’t identify the specific behavior. If you are going to bomb throw incendiary words at coaches, you owe it to everyone involved to explain the basis for that. If you aren’t confident enough that your facts justify your opinion, don’t state your opinion and then jump down the throat of those who ask you to support your serious allegations.
But let’s say a pattern of inapppropriate behavior develops despite your best efforts. The parent absolutely has an obligation to know it is happening and to stop it before it gets out of hand. Hopefully, everyone is asking more penetrating questions of their children than “how was practice” before moving on to the equally unhelpful question “how was school”? Ask specific questions that require them to provide answers with specific details that they can't just blow off. What did you work on today? Man, it looked like your coach was in a bit of a mood last game, what’s the deal? How is Bella doing? Coach seemed pretty frustrated with her. What did they talk about? Your teammates looked pretty grim walking to the car after practice; what’s the deal? Why was Bella crying? And don’t always ask soccer questions right after soccer practice. Get them when they’re in a chatty mood. If you can’t get out of your child that her coach is verbally abusing her, it is time for self reflection.
If you are afraid to do anything about a dangerous situation because you are worried about harming your reputation or that your daughter will get blackballed, or you are videotaping a coach to prove to others that your daughter is in a dangerous place, man you have lost perspective.