I think there are three main threats humanity currently faces.
(1) nuclear war. In any one year the chances of a serious nuclear war are quite small; however the consequences will be global destruction of human civilisation. For many people under 40, this is a black swan scenario, an event which will take them by surprise.
(2) global warming. This is an impending global disaster. Although in theory we know how to stop it, in practice we are incapable of stopping it. The only real question is – how soon?
(3) we don’t even really have a name for this yet. It includes the enormous changes which social media is causing to our global civilisation(s). It includes the known and unknown outcomes of advances in AI. And it potentially includes other technological changes we do not even know are coming. Maybe it is about the mismatch between our evolved behaviours and abilities and what technology is able to provide. I have no idea where this is all going but I don’t see humans outliving it.
We evolved with certain environmental constraints. We figure out how to do away with those constraints. Now we live in a world for which we are not evolutionally adapted.
For example we evolved with a constraint of food scarcity. We learned how to do away with that constraint. Now most of us live in in a world of food abundance for which we are not adapted. Creatures which are poorly adapted generally die out.
When did the so-called Anthropocene start? Not 1952 as some suggest, trying to motivate people into political action with a fake geological age and a fake start date. In my opinion, anthropological global warming started together either at the start of the iron age or at the start of farming or maybe of cities. We first smelted iron, later steel, but a blink of the eye later we were on the moon, blink of the eye in geological time. Maybe from the first use of iron it was inevitable that we change the climate.