Your line of thinking is exactly what's wrong. The fact that life emerged on earth shortly after being able to sustain life says absolutely nothing about likelihood. It could be a very likely thing. Or it could be a 1 in a 10^35 miracle that happened due to an insanely low probability event involving gamma rays hitting chemical reactions in just the right way. Until we solve abiogenesis and can demonstrably evolve life from abiotic matter, or observe other planets with life on them, this is all speculation.