Why do the majority of people not include gang shootings if this is an accepted definition of mass shooting?

The reality is gang shootings are why there are 200+ mass shootings a year in the US.

"Crime violence research group Gun Violence Archive, whose research is used by all major American media outlets, defines mass shooting as “FOUR or more shot and/or killed in a single event [incident], at the same general time and location, not including the shooter,” differentiating between mass shooting and mass murder [killing] and not counting shooters as victims."

I'm really looking forward to a certain individuals reply to this. Let the BS begin and as always attempt to make himself sound more educated than he really is.