Although the Fermi paradox is questionable, I find the gedankenexperiment of a Great Filter interesting.
Most proposed filters take the form of a falloff, where the path from basic life to interstellar communication includes steps that are improbably reached, and either we are very special or heading towards a cataclysmic event.
I prefer to think successful civilizations eventually learn they cannot last if they concentrate resources, that only decentralized power is resilient enough for long-term survival. So the universe is full of long-lived societies asymptotically advancing technologies but never investing in “big enough” to expand beyond their neighborhood.
Nothing about this solarpunk scenario is inevitable, though. I worry that we are one of the learning-resistant ones heading for a traditional filter. We benefited from an entropy-defying ecosystem that enables the rise of complex society and technological advancement. That same advancement, though, works against the ecosystem, disturbing it in ways that damage the foundation upon which we have built our lives.
There are plenty of candidates, and we’re plenty worried about the big ones. Since I listened to a 2020 episode of Radiolab, my “favorite” risk has been the spread of fungus infections enabled by climate change. I’ve been thinking of this as The Mushroom Filter.
So when we received a sourdough starter in August (before The Last of Us popularized fungal fear), I remembered that the particularly scary Candida auris is a type of yeast. So I proposed naming our starter Fermi. Shannon chastised me for being too dark and also embraced the name. We now regularly enjoy incredibly bread that she’s learned to bake with Fermi.