Thank you for googling and reading. That is a good step towards avoiding a repetition of what was said earlier.
I'm trying to point out problematic *actions* here, rather than people. I understand you're a human who probably has a variety of thoughts on gender, as well as the ability to learn and change; I'm telling you that some behavior was unacceptable and needs to change. In particular:
1. If a topic (eg. "sexual harassment at conferences") makes you uncomfortable, don't change the subject (as aleXXX did) to one that seems easier to trivialize (transsexuals).
2. Don't trivialize transexuals. Also don't trivialize racism. Nobody even mentioned that. You can easily tell that the people involved in the topic take it seriously; starting your contribution by a trivializing statement is equivalent to an insult, and you can probably guess that.
3. Don't throw in innuendo about "real motives" when someone relates their their own experience or identity, or that of their friends, relatives, loved ones.
4. Don't make it someone else's problem to inform you of things you can learn yourself. It's a sign of respect for a topic to do independent reading on your own time.
5. Don't tell someone that they'd be better listened-to if they only spoke less directly to the topic at hand. You demonstrated how seriously you take less-blunt talk earlier: by trivializing. That is *why* I responded bluntly and why I'm continuing to be direct.
Again, thank you for hearing my earlier remarks and responding by reading. There is plenty more to read if you're interested in adapting your behavior; see the link I left above to the "resources for men" page.