Life did not die out on Earth, or on any particular environment where it previously thrived, in spite of major changes in temperature, composition of atmosphere, and multiple large scale disasters. This suggests life is very resilient. Every time life is wiped out in some part of Earth, it is quickly recolonized.
Be careful of anthropic bias here. Taken alone, the argument "life did not die out on Earth" is invalid because if it had, we wouldn't be here. However, the second point, that when some evolutionary niche is wiped out it is quickly colonized, would seem to me to be valid, since it suggests systematic resilience to disaster.
I think my reasoning is valid even with anthropic principle. If life wasn't resilient, we should expect by anthropic principle to have no major disasters in the past, not to have survived major disasters.
We have a sample of one modern human civilization, but there are some hints on how likely it was to happen.
Major types of hints are:
Data for:
Data against:
To me it looks like life, animals with nervous systems, Upper Paleolithic-style Homo, language, and behavioral modernity were all extremely unlikely events (notice how far ago they are - vaguely ~3.5bln, ~600mln, ~3mln, ~200k or ~600k, ~50k years ago) - except perhaps language and behavioral modernity might have been linked with each other, if language was relatively late (Homo sapiens only) and behavioral modernity more gradual (and its apparent suddenness is an artifact). Once we have behavioral modernity, modern civilization seems almost inevitable. Your interpretation might vary of course, but at least now you have a lot of data to argue for your position, in convenient format.