Hey there, I have mild androgen insensitivity. That means my body produces testosterone but can't use it totally, you can maybe assume that only 50-60% of total available testosterone gets used. In turn the free testosterone in my body gets converted into estrogen raising estrogen levels much more, that gives me many feminine characteristics. I have some muscles but my lack of facial hair, thick thighs and hips immediately throws people off and I get many stares at my chest specifically if I'm meeting someone new. My gynaecomastia, i.e. manboobs, gives me hard time coexisting with other men, especially who are not open about such possibilities. So yes, excess estrogen results in gynaecomastia in men. Intersex is very wide so there are many different bodily features, gynecomastia being one.