given the time scale of the duration in which a major impact event is likely humanity's technology will have advanced radically beyond which we could possibly imagine
No, actually, if everyone chooses "invest in other things" over "invest in technology", then it won't happen. If it will happen, it will be because of technology investment, not as magic that occurs independently of them.
It's impossible to imagine how humanity would stop investing in technology or would only invest in technology that would not be related to space travel