Here is an interesting note about another refuted counter-argument against intelligent origins of life. This flawed argument states that biological life cannot be likened to human artifacts because humans cannot create autonomous self-replicating, self-deploying systems. In this video quoted in the note this argument is dismissed by demonstrating a self-folding autonomous walking robot. According to the inventors, the self-assembly is inspired by biological systems and origami.
The only thing I would add is that this argument was actually debunked as soon as the first computer virus was written in 1981 to attack Apple machines. Viruses are persistent and self-replicating malicious computer code.
So if artificial systems, that are organizationally a lot simpler than protein life and are known to have intelligent origin, can replicate and deploy themselves, then the considerably higher complexity of protein life testifies all the more to a high likelihood of its own origin being intelligent.