What ethnic or group solidarity is allowed?

For an example, see

https://www.politico.com/news/2024/07/22/kamala-harris-zoom-fundraiser-00170452

" “We need to defend our sister everywhere”: Inside the organizing call for [Kamela] Harris"

In comparison, suppose someone was to say 

"We need to defend our brothers everywhere", 

referring to white males.

Can you imagine the reaction?