I didn't mean to imply that the right didn't have its own doomer narratives. The current hotness seems to be demographic predictions of doom, "great replacement" theories, etc. I'm very skeptical of those too.
What I was getting at though was -- I think the left allows its doomer narratives to be intellectually paralyzing. If everything is going to crash and collapse and burn, there's no need to actually try to solve problems or offer a compelling narrative about the future.
The right doesn't do this. They feed their own doomer narratives into a "rage against the dying of the light" narrative. This results in all kinds of ugly racism and persecution and authoritarianism, sure, but it doesn't lead to paralysis. So, as I said, they win by default. In the battle for hearts and minds, they win if they're the only ones that show up.
Edit:
Another way of saying it would be to say that for the left its doomer narratives are demotivating, while the right treats its doomer narratives as motivating.