I've lived and experience life through this body (115kg Samoan, Male) and this context (NZ born, living in a metro city, working in Tech).
That experience is going to be different to anyone else, no matter how many of those things we have in common i.e. age, ethnicity, city etc.
I don't know what it's like to be you- I have an idea, I can empathise, theorise and hypothesize, but I don't really "know".
What I do know, is the difference in the things that I present (size, colour, age) elicits certain responses from people who experience "me".
Those experiences aren't always positive ones.
My size can make people uncomfortable, and feel intimidated. And I don't have to do anything.
My size also makes some people feel safe and protected. Again, having done nothing to make this associated explicitly like saying "Hey, I'll protect you" or "I'll keep you safe".
The same way looking the way I do, has had people doubt I know what I'm talking about in technical areas, or would double check my work or understanding where another person who doesn't look like me, would never be checked.
When a space is created, for people who have a shared lived experience (size, ethnicity, income level, physical disability), it's hard to reconcile admiting people to that space who don't share that experience.
We may share some traits, characteristics, but a space created on a specific lived experience may suffer from losing focus on that experience.