Or there are fewer civilizations than we expect, or something is wiping out civilizations once they go to space, or most species for whatever reason decide not to go to space, or we are living in an ancestor simulation which only does a detailed simulation of our solar system. (I agree that all of these are essentially wanting, your interpretation makes the most sense, these examples are listed more for completeness than anything else.)
Or there are fewer civilizations than we expect, or something is wiping out civilizations once they go to space, or most species for whatever reason decide not to go to space, or we are living in an ancestor simulation which only does a detailed simulation of our solar system. (I agree that all of these are essentially wanting, your interpretation makes the most sense, these examples are listed more for completeness than anything else.)