Note that Canada is still on fire, the affected area is larger than many US states, and now that the smoke isn't blowing south into the state where I live, we aren't talking about it. So, maybe a little truth to that. We, as resource-constrained individuals, have a hard time focusing at things distant from us for an extended time. It's a pro-local-survival bias, so has an evolutionary value.
However, it's also a blind spot that can be ruthlessly exploited by those with something to hide.
I'm assuming this is more a comment on the modern news cycle than about Reddit. Hell, most things barely last a few days outside of their immediate time frame, let alone a week.