I don’t believe “civilization” is as resilient as you think. The late bronze age collapse, and all the mystery surrounding that event, did indeed take place over hundreds of years in a vast “global” society. I very much doubt anyone in that society could have predicted such a spectacular collapse. It’s not really a disputable fact that civilization has collapsed many times before and probably will again before we have to worry about these silly “billion year” concerns - maybe let’s just focus on the next 200 years?