Here's my take.
AAVE is something that a lot of black people do not want white people/non-black POC to use, but with good reason. The words they use that are apart of AAVE have been used for decades but are being mistakenly coined as "trendy" and "stan Twitter language" mostly by white celebrities. The main problem black people have with white people using AAVE is the double standard that comes with it. Online and on social media it is shown as being used as trendy language, and to be funny. When it comes to real life though, black people are frowned upon and called less intelligent simply for using AAVE. The same does not go for white people though, because with the privilege they have, they are just seen as trendy for using AAVE. This just goes as another part of African American culture being taken by white people. It is seen as bad or trashy for black people to have their own culture, but only is it seen fine to people when white people take it. Not to mention how these words are commonly taken by white people and changed to where the original meaning is not even present.
Tldr; Black people are totally valid in not wanting white people/non-black POC to use AAVE, because it is just another part of their culture that is being taken and becoming "acceptable" for white people, but not even for black people to use due to decades of misconceptions and racism towards black people for their own culture.