>Betelgeuse is calculated to be 640 light years away, and effects on our solar system would likely be minimal given the distance.
Yes, that is what anon is pointing out.
It would be a 'killing bolt' (supernovae are decidedly lethal events for those involved) that would shine in the night (supernovae-like observations have been recorded for centuries), but would not kill (as you said we're too far away to care).