I'm not refusing to believe in the hypothetical reality. Of all the hypothetical realities I can conceive, "actually aliens" is the one I want most to be real. I want to live in that world, and not just see it in fiction.

What I am refusing to do is believe that hypothetical reality to be more likely than it is, based on the evidence (or lack thereof) presented and what it does or doesn't actually prove. I'm slotting it in the rank it deserves, which is slightly ahead of demons in likelihood but still less likely than everything else.

But yeah, the likelihood that it's aliens is not entirely zero.