I think that depends on how you define ‘civilisation’. My inclination is that most people would say civilisation has ended if life is drastically different to how they perceive their life/world they live in. Think ‘civilisation as we know it’ rather than a dictionary definition.

However, I disagree that it’s not an existentisl threat, if only on the basis of possible crop failiures on a massive scale (reduced crop yields are a global issue already). Don’t underestimate the impact of food shortages on everything else, we in the west have become accustomed to easy access to food.

I recorded a film off the tv channel Sy-Fy a few years backcalled AfterDeath (not the 2023 film that comes up in a search). It’s possibly not that obscure, but I believe it was a low budget film so maybe not at all well known. Anyhow, it didn’t record all the film for some reason so I have never seen the end (last 15min or so), but despite the clear lack of quality it had an interesting premise (a group of young people who wake up in a beach cabin but apparently in the middle of some quasi-nowhere). I was intrigued as to how the approach to playing out the scenario would end but maybe I enjoyed it more for not having been able to see the ending if it was z bad one!

I remember this! Takes me back a few years, and some, when I had an Atari ST!