>>212546793They collectively refer to the various lions used over the years as "Leo" as a mascot, though only one of the lions playing Leo was actually named that, the current one, used since the 50s. This one was named Jackie and was the first one to be filmed roaring for the camera.
Also the roar sound used is a tiger growl, not a roar, roars sound very different, and lion roars are low and rumbling