Would it? Perhaps we wouldn't be so cagey around racist grandparents (or their equivalent) if they weren't going to die soon.

I think it's an incredibly pessimistic view of humanity to suggest social change can only come about through death.

Moreover, I think this argument tends to come solely from people trying to excuse death, rather than any kind of reasonable analysis.

The problem is that in a world without aging and natural death, your racist great-great-grandparents have (effectively) all of the resources and power, and therefore no reason to listen to you at all.

Yes, this is a pessimistic viewpoint, but I think it's also a realistic one.