What do you mean?
The space for you to thrive is out in the real world in your real life. You can't really compartmentalize thriving. You're either thriving or you're not.
That's not to say you can't have challenges in certain aspects of your life. You certainly can. You could be going through a divorce or have a troubled kid but be doing great in your career.
But a safe space for men to go to for support and support other men with men's issues, maybe be learn some life/relationship skills you don't have or need to ahore up....how is that oppressive? Oppressive to whom?
AL-ANON is the same sort of thing. Addicts supporting addicts with sobriety without shame or judgement.
Rape survivors have groups. Cancer survivors. There are even women's groups, though not as many as there were in the past. Parents support groups for terminal children. Groups for suicide. The list goes on and on. Mom groups. How could I have forgotten those.
Would you say any of those are oppressive? Oppressive to whom?
If being a man is so difficult that you need special emotional support, especially from others like you (a man) because only they can understand what its like and what you have to go through to be able to thrive in society, then yes, absolutely, you should have them.
And they can be private. Nothing wrong in that.
As long as you're not breaking the law, doing or setting out to do harm.