I think that's just some form of confirmation bias you've formed, as I've never noticed that. I will say most of my offices have been multi-cultural, but even then, I've been on and led teams of white-only males that never succumbed to even posting these gifs. I guess guilting people into censoring their choices is a point of action, but I think the entire process should just be faded out. Slack admins don't need to allow these plugins. Theres nothing stopping people from literally going to giphy.com or whatever, but that's not why it's popular -- and it's definitely not why FB is shelling 400 million for it.
they ruin all flow of conversation and serve as distraction rather than substance. It's mindblowing to see some Discord and Slack channels just bombarded with fancy moving pictures. It's particularly worse when people won't use the "Thread" feature to contain reactions and sub-conversation to specific comments. It can result in lost information if people aren't careful, but it's almost always better than littering the feed with semi-relevant reaction gifs.