TBH the simulation feels quite deceptive without the risk of people dying, or immunity waning over time.

I mean I assume the intent was to recreate the original without changing it, which I can understand, but the premise of the simulation in and of itself is something I have critique of.

The purpose of the article was not to simulate how COVID-19 or any other disease would spread in the real world. It was just to give people a nice way to think about network effects and exponential growth. That is why I didn't an add any number of other complications like masks or vaccines. I had no idea how well they would work, and people still don't know. Quarantines and social distancing are more about whether people come in contact with each other in the first place, so they were appropriate to include.