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I may be a dumb layman, but that argument seems too tidy and absolute to me - wouldn’t it suggest, for example, that viruses could never appear because they’d b

• Shorel 1mo ago
  Viruses are not newly appearing forms of life, they are co-depending on the already present forms of life and they reuse some of their machinery. Viruses are the opposite of starting from zero, they start from a functional organism and stop existing if the base organism gets extinct. However, reading other answers, it seems the great oxygenation event is an even stronger argument against basic life appearing again. They would get oxidised and die.
• Intralexical 1mo ago
  Nope. It would suggest that new viruses could not spontaneously appear from abiotic matter, because they'd be outcompeted by existing viruses. Which may well be true. We don't know where exactly viruses came from, but one of the leading theories is actually that they are the descendants of bacteria which outcompeted other bacteria. When a parasitic bacterium sheds more and more of its own metabolic capabilities, because it's more efficient to steal those abilities from its host cell, it evolves in a way that looks more and more like a virus. "More evolved" or "more advanced" in this case doesn't mean "bigger" or "more complex". You can say viruses are equally evolved as bacteria, meaning they've spent equally long being optimized for their ecological niche.