That's true in the long run, however in shorter time frames there's no reason that a gene drive couldn't establish itself in a local population. You bring up v

That's true in the long run, however in shorter time frames there's no reason that a gene drive couldn't establish itself in a local population. You bring up viruses; the aim of a virus is survival, and wiping out its host is counterproductive. The most successful viruses are usually comparatively docile to prolong carriage (most extreme examples are endogenous retroviruses).