You didn't actually read the OP, did you?
The OP was about a potential reason why there were no female Space marines, not asking why there could not be any.
Yes, I did read the OP. At the end of their post they opened the floor to 'Thoughts, or disagreements?'. Which is what I put forth.
My post, if you read it closely, was to the thought
that of all the odd points of lore in the 30/40k universe that people accept without question- why is it that the 'no female astartes' seems to be a sticking point in people's craws when the lore is very clear on the matter. Basically, I was asking why is it that this bit of established lore seems to be always questioned over others. It is why I prefaced my post with the allusion of the soapbox- meaning I was about to air a personal view on a topic (something that the OP encouraged at the end of their post).
After that I went on to touch on the secondary topic(s) raised in the thread, referencing points of cannon and offering my own personal opinion on it.