I think I do see your point. Exclusionary safe spaces can also create pressure within them to conform to some set of expectations for your identity. In that way, they set up a hierarchy based on who is most vs. least able to conform.

Absolutely true. They also create an illusion of safety. A ‘this group of people won’t harm you’ vs ‘this group will’ which simply isn’t true.  

Which doesn’t mean you can never practice exclusion in safe spaces. Good examples are organising a trans-only sauna where people can get naked without cis people staring, or doing healing work with an invitation-only group of people that know and trust each other. 

But as a tool to create safer communities, I think exclusion tends to do more harm than good, especiialy when it is seen as the only tool needed and especially when it is accompanied by a vigilant effort to figure out who is queer enough / woman enough / disabled enough etc to fit in the space.