How many Diversity training classes/seminars have you taken? Did they tell you anything you didn't already know? Did you accept that if you are a white male you may have held back minorities. That being white got you to your position, not your hard work and knowledge.
I was paid by two levels of government to provide cross cultural training. I have to agree with you and I will explain why. If people genuinely want to learn about differences in cultures and how this may impact on communications, perceptions and lead to misunderstandings that can be useful. Diplomats, corporate executives, military, get that kind of training and it has a lot to do with protocols as to what is considered rude, impolite, inappropriate and non verbal body language. I am sure you know about that. It has specific purpose. Its also used by police and other investigative agencies analyzing human behaviour. It can be very helpful.
However when we speak of diversity training, the word "diversity" is NOT necessarily concerned with cross cultural communications or psychology which I taught. Its about political concepts relating to perceptions of unfairness and who is unfair and so it is often not in resolving misunderstandings and may in fact reinforce them.
I have trained police, teachers, nurses, mental health counselors, etc. We would teach very specific things like how in some cultures time reference is far different or how body posture or mannerisms is different. In some cultures for example people when looking at authority figures bow their heads, engage in excessive smiling, avert their eyes, nod up and down to mean yes not no. Different cultures have different non verbal mannerisms and use different tones of voice for situations you and I might not. Our focus was on the immediate hear and now and preventing misunderstandings in the moment. We also were vert clear that what we taught was not a one size fits all approach.
I am of course over simplifying it. Diversity training though focuses on the politics of power imbalance.
Diversity training is a concept attached to undoing what is seemed as unfair power imbalances. It starts off with genuine intent to address a perceived unfair relationship but then often evolves into the exercise of simply reversing the order of who abuses who without ever addressing the misunderstandings.
It all comes down to the motives of the people behind the so called "training".