"Mere existence" refers to the state of simply existing or being alive, without any additional qualities or attributes that would make it special or noteworthy. In other words, it implies a basic, unremarkable state of being. It can also be used to suggest that something or someone's existence is significant in and of itself, even if they don't possess any other qualities or characteristics that would make them remarkable.

Ahmadi is correct. I just want to add that another way of phrasing this idea (or at least a very similar idea) is to say, "just being alive became effortful".

Here politics means mind planing. Or the way by which we treat people for ones benefits.