It is a reasonable conclusion. Resource limitations means civilizations, burn up too much of their energy/materials before they ever get truly space bound.
They could all be just like us. A few space probes manage to escape the energy well but they are so small that no one else ever detects them again. I mean, it is not uncommon to sight life ending asteroids days after they have passed earth, the odds of us detecting any sort probe/device the size of a fridge - is nearly zero.
Best analogy I heard came from Stephen Harrod Bruhner. Civilizations are just like plants. A plant is at its fullest just as it is about to produce seed and die off. During the peak of our energy use, we have been sending probes into space. It is a neat thought experiment.
They could all be just like us. A few space probes manage to escape the energy well but they are so small that no one else ever detects them again. I mean, it is not uncommon to sight life ending asteroids days after they have passed earth, the odds of us detecting any sort probe/device the size of a fridge - is nearly zero.
Best analogy I heard came from Stephen Harrod Bruhner. Civilizations are just like plants. A plant is at its fullest just as it is about to produce seed and die off. During the peak of our energy use, we have been sending probes into space. It is a neat thought experiment.