Sure... Darwin was writing almost 200 years ago. He knew nothing about genes, DNA or microbiology.
You point out that Darwin "doesn't know what he is talking about. And you are absolutely correct. But don't be too hard on him... he lived in the 1800s. Compared to scientists today, Darwin knew less than a typical third grader understands today. That doesn't take away from the importance of the theory he first popularized about natural selection... but science has come a long way since then.
In other news, The airplane developed by the Wright Brothers was pretty crappy. It didn't go very fast and it was pretty dangerous. That doesn't take away from their accomplishment either.
I am still unclear about whether the thrust of your post is to talk about Science or about History. You tagged this as "Science"... but you seem to want to talk about history.
If you want to talk about the science, you should talk about what we have discovered about evolution in the almost 180 years of investigation since Darwin. We now have sequenced genomes, studied geological records, looked at changes in DNA, learned how to see our ancestry and understand genetic diseases and develop new drugs.
If you goal here is to make a comment on history... then sure, Darwin didn't know very much compared to what we know today. But that is to be expected and his basic idea turned out to hold up and be shown to be correct after hundreds of years of study, experiment and development.