Do slave owners get a seat at the table when discussing whether or not and how slaves are oppressed?
Do white people who support Jim Crow laws get a seat at the table when discussing whether or not and how black people are oppressed?
Does a religious majority get a seat at the table when discussing whether or not and how a religious minority is oppressed?
The argument is: those that are not affected by the oppression discussed (who may even be doing the oppressing) simply cannot have an objective discussion on whether or not and how a community is being oppressed. How do you know what that oppression is and feels like to tell someone that they are not being oppressed? Therefore, where a white cis-het male's opinion is productive is only when discussing how they can help-- not when discussing whether or not that oppression exists.
In the same vein, I am male. My opinion is not productive when discussing whether or not and how women are oppressed. Consider this scenario: male politicians are deciding on laws that govern women's bodies; women say they are oppressed; men say no you're not oppressed. Do you see why men's opinion are not productive here? My opinion only matters when discussing how I can help women feel less oppressed.
At the end of the day, you have the freedom and right to discuss all you want. But ask yourself, is your discussion productive or destructive to someone else. Your arguments will never convince an oppressed community that they are not oppressed, that's gaslighting. It will only convince other unaffected people against them-- which is why it's destructive to discuss the existence of oppression when you are not the oppressed.