> existed in an ecosystem for tens of millions of years without evolving into some sort of important niche These mosquitos are a man-brought invasive species,

> existed in an ecosystem for tens of millions of years without evolving into some sort of important niche These mosquitos are a man-brought invasive species, so that argument doesn't fly. + You're already mentioning we don't know what effect species going extinct can have... But that's the point, countless species are already going extinct anyway, there's literally zero reason why you would worry or care more about keeping this one.