That is a black-or-white fallacy. You don't need to have a group being historically oppressed in order for discrimination.

Oppression is about liberty for which there is little proof which gender has more. The number of working profession which is excluded for women is exactly the same number for men in countries where both women and men are employed in similar numbers (such as Sweden). Men are equally or even more forbidden to enter areas which are assigned female roles, and the studies that look at this (such as one about the teaching profession) acknowledge that feminism has made some minor progress to make it acceptable to women to move to typical male roles but not the reverse.

Womens right activist has fought a long time that their movement isn't about anti-men world-view, so why is it acceptable to draw that same conclusion on all men's rights activist?

You're likely correct, but isn't is a bit sad that this is the case? That unless it is generally accepted (regardless of whether or not it is true) that men are discriminated against based on gender in some situations, that the only other possibility is misogyny?

On whether it matters....I had a long conversation on the phone with an old friend yesterday, he is going through a divorce and has so far been bankrupted, been dismissed from his job (due to being obligated to take too many days off to prepare for court), he only gets supervised visits with his son, etc. I predict he will commit suicide within 5 years.