Why do so many people lecture me on what it’s like to be a straight white male, and why is what they say invariably unlike my life?

Do they tell other people what they should be like due to their sexuality, skin color, and sex?
Why do they presume to know so much about me and what motivates them to tell me about my life?
Why do they tell me so much more than they ask me?
Why do they imply a homogeneity among straight white males?
Why do they seem to want me to agree with them that my life was how they said, not how I lived it than for them to broaden their views?
Why not treat me as a unique person?
One small example of many is saying things like “now you know what it’s like.”
I’m asking because it keeps happening. I also get treated a lot like I’m stupid and ignorant of how anyone lives who isn’t rich or privileged.

I think we both know why. A more important question is, why do you associate with those people? I hope you’re getting something out of it, too.
I get it from so many places, the pattern doesn’t fit stereotypes. If I stopped associating with everyone who did it, I don’t know who would be left. Some people do it intentionally but I think some don’t realize when they do it.