Earlier quoted context omitted.
By this criteria - all papers that extrapolate are BS papers. There’s a ridiculous number of stars in the sky - no matter how low you put the odds of intelligent life, you will still end up with more than 1 civilized species in the universe. This is, at least for me, the primary utility of such extrapolations. And eventually - extrapolations will be tested.
Extrapolating from multiple good data points and making up a number based on zero examples are absolutely not the same thing.
Coming up with an estimate, calling it a theory and being clear about the fact that it’s not a sure thing ? That’s perfectly fine.