I think ribosomes have a lot in common with machines. They use energy to accomplish a task (assembles proteins). This would seem to put them in the same category as artificial molecular machines like rotaxanes. I don’t think there’s a huge gap in our understanding of how either systems identically functions independently. Yes, ribosomes exist as part of a larger context, but they can be removed from that context pretty easily and understood as individual molecules quite extensively.

In your view, can machines even exist that haven’t been created by people, definitionally? I, personally, don’t see the relevance of intent but that seems to be the only distinguishing factor here.