It sounds like you believe that big labs are irresponsible. Wouldn't this support the notion of creating a pause mechanism for use in an emergency, as advocated in the OP?
>You're not convinced by the evolutionary argument I made earlier, but the reason you gave is "we're too far ahead". I don't think this justifies that the pattern will cease soon, because it always looked this way to the frontier species, for millions of years.
If you don't see humans as qualitatively different from any intelligent species which came before us, I'm... not sure what to tell you? Like, can you name any intelligent species before us which triggered a mass extinction or climate shift, to the degree that our species has? Did any intelligent species before us practice large-scale agriculture, dig up chemical fuels, or visit the Moon?