[VadeRetro]

... no living organism can ever spontaneously arise from lifeless matter ...

Have fun fulfilling this part of the prediction. You will have to anticipate every possible scenario for unguided abiogenesis.

[unlearner]

"Have fun fulfilling this part of the prediction. You will have to anticipate every possible scenario for unguided abiogenesis."

That part is what makes it falsifiable. We do not need every possible scenario, just one, proving my hypothesis wrong.

Meanwhile, every instance in which people are able to assemble life (when and if this actually happens) will serve to support the hypothesis.

It is testable and falsifiable. Is it simplistic? Maybe. But simplicity is usually regarded as a plus for scientific propositions. Is it elegant? Perhaps, like beauty, this is in the eye of the beholder.

Until some other evidence is found to support abiogenesis or some deviation in the laws of causality, there is no competing hypothesis explaining the origin of life.