“It seems that we mainly disagree about what constitutes discrimination. In my opinion, it is about opportunities. When 90% of the developer jobs are performed by men, it is really hard for me to see how men as a group can be disadvantaged.”

If e.g. 95% of the qualified people are men, but only 90% of the accepted applicants (just making up numbers here) then clearly there is discrimination against men. Outcome by itself says nothing about discrimination.