Of course, memicide is where some meme comes along and kills all its hosts. We've seen too many cases of these cults that take the lives of all their members. It should come as no shock that repression and racism also fit what we mean by a kamikaze meme. Cultural Speed Bumps. Culture often takes hundreds of years to make a change.
Slow change is the rule.
In the age of instant worldwide TV, radio and cell phones, we might guess that ideas would spread faster. But most cultural change still moves at a slow pace. And just because we can fly to any spot on the globe in a few hours doesn't change this. Shared ideas seem to change at their own pace. For example, witness the long story of civil rights change in the United States.