Like most interesting conspiracy theories, there are kernels of truth mixed in among the hyperbole, misdirecting questions, and plausible-sounding misinformation.
"...no one has been able to identify the actual medical cause of the 1918 Flu..."? Hello--the entire genome was published in the prestigious journal Nature not long ago. And then another scientist recreated the genes, and with the help of the CDC--partly for their expertise, and partly for their bioware-level containment labs, I'm sure--actually produced live virus samples from it. The so-called "Spanish Flu" appeared everywhere around the world at once? Also not true. The spread was fast, yes, but not "...spread around the world in days..." as this guy claims.
Fever the human body's only defense? Then why does he go on to describe other mechanisms the body uses to destroy the virus? And viral pneumonia is relatively uncommon in flu cases. It's usually secondary bacterial pneumonia that hospitalizes and kills people who catch influenza. However, unlike your garden-variety flu, it is true that Spanish Flu caused massive lung damage, but that was regardless of whether aspirin was taken or not.
The little history on Bayer and aspirin was interesting, although I have no idea if that part was even true. And this guy claims to be the only person in the world to figure out the etymology of the world "aspirin"? Brilliant! While it's true today that you can't label your drug as fever-reducing if you didn't originally get it approved for it, I doubt that those restrictions were in place at the turn of the century. Back then, snake oil still flowed freely.
Like Blast said, according to this guy's logic, people should have been dropping like flies for decades. Even now, in our litigous society, do we see warnings on aspirin bottles against using it for fever because we might die a horrible death, choking on our own fluid?
That said, there is is a place for fever-reducing medications, particularly when it is high. However, using aspirin to bring down a fever has been shown to pose a risk for children and teens for Reye Syndrome, and the label warns you about it.
Anyway, a somewhat entertaining read, but there's no substance to the story. And definitely don't swear off aspirin or any other fever-reducing medication because of it.