Black death.
Bubonic plague.
Smallpox.
Malaria.
Measles.
Polio.
There have been many more virulent and many more destructive diseases than this one. Malaria in particular has been so destructive over thousands of years that it has modified human populations, forcing observable natural selection for traits such as sickle-cell anemia. https://en.wikipedia.org/wiki/History_of_malaria
And in many developing countries, there are tragically many deaths caused by poor sanitation or healthcare.
However, this is a disease that has - even with incredibly draconian lockdowns and a global effort from every country to combat it - tragically killed nearly 350,000 people in a matter of months. And this is often in countries with state of the art healthcare systems, and every effort made to keep those people alive.
And as another commenter pointed out, this is often in countries not used to such scale of health disasters, as they have healthcare and good sanitation. Ironically, I read that things like air travel and holidays actually worsened illnesses like this.
Imagine if we'd simply let the diseases run its course.
The thing that baffles me is the US - advanced Western nation - with a death toll of nearly 100,000 people. How is that even possible?
I am hoping we've seen the worst of it.
AIDS has killed around 34 million people since 1981.
That's on average 100k deaths per year since 1981.
Right now we are in our first quarter of covid19 and the official death count is at 340k.
So I suppose somewhat like the situation in the US with COVID-19 today.
Polio.
"On Saturday, June 17, 1916, an official announcement of the existence of an epidemic polio infection was made in Brooklyn, New York. That year, there were over 27,000 cases and more than 6,000 deaths due to polio in the United States, with over 2,000 deaths in New York City alone.[15] The names and addresses of individuals with confirmed polio cases were published daily in the press, their houses were identified with placards, and their families were quarantined."
https://en.wikipedia.org/wiki/History_of_polio
Measles too. These are diseases that hit the western world, the rich countries, killed thousands, in living memory. They causes panic. They caused quarantines. They caused social change. Polio lead directly to the disability rights movement. Wheelchair ramps as mandatory in all buildings: that's from polio.