These are questionable assumptions. Herd immunity thresholds seem to be closer to 20-40%:
https://arxiv.org/pdf/2008.08142.pdf
https://www.medrxiv.org/content/10.1101/2020.04.27.20081893v...
Moreover, fatality rates are not 1%. Current best estimates are ~0.6%, overall, with a strong dependence on age:
https://www.medrxiv.org/content/10.1101/2020.08.24.20180851v...
https://www.medrxiv.org/content/10.1101/2020.07.23.20160895v...
https://www.thelancet.com/journals/laninf/article/PIIS1473-3...
The young (i.e. those under 30), in particular, are at almost no risk of death:
https://www.franklintempleton.com/investor/article?contentPa...
"Keep in mind that 9% of people have suffered a crippling illness that lasts several months."
There is no evidence for such a claim. If you're referring to the people who spend time in ICUs, on ventilators, etc., these people represent a small fraction of the most severe examples of known infections (i.e. less than 9%), which themselves represent only about 1/10th-1/20th of the total number of infections:
https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/comm...
The vast majority of people have mild illness, akin to a cold.