When I read about features like this I open my mind to the various forms of abuse it is addressing; I have to imagine, because I don’t have a Twitter account, and therefore am not directly exposed to the behavior they are attempting to adjust.
Okay, with that in mind: what is the purpose of hiding the user card? Does the user card on Twitter offer vital information or a menu of options to interact with the user? Please lay out for me how this benefits the “unmentioned”. 
“Unmentioning” = 
