If the training were really good, led by a skillful trainer, with employees who were genuinely interested in thinking through what a “microaggression” is (and I heartily agree with @Ulfreida that it is an awful term) it would not teach that lesson at all. It would lead to thoughtful discussion and new insights by everyone. Whether the OP’s training was meaningful, or just box-checking, I have no idea.
I sense that some posters in this thread (not singling out any one) do not understand this: Most microagressions are completely unintentional, and the people guilty of them are often blind to what they are doing. If you talk to them, they’ll insist they are good-hearted egalitarians, not the least bit sexist, ageist, racist, ableist, etc. And in their hearts, that may very well be the case. But that doesn’t mean they are innocent of unconsciously perpetrating stereotypes, and doing hurtful, exhausting acts toward others.
If you are not a member of a group that is subject to microagressions, it can be hard to understand the toll they take. I used the word “exhausting” for a reason. When you are constantly being reminded that, consciously or not, other people think of you as belonging in a particular box or not quite as smart, you can never let down your guard. You have to prove yourself all the time, unlike “the boys’ club” members who can kick back and let loose with each other because they know their station in life is just fine.
I repeat, many perpetrators of microagressions are not consciously intolerant. They truly mean well, and they believe they are not bigoted. 95% of the time, they probably don’t behave in a bigoted manner. But that other 5% of the time … well, if you haven’t lived it, you should listen to the people who HAVE without dismissing their concerns as trivial, or unimportant because the microagressor is a “good guy.”