You realize every other time it rains in NYC, they dump raw sewage into the ocean and there's an uptick in people who get sick (swimmers) as a result?
Almost every major city in the US has this problem.
So I must disagree. I don't think it would be worse than our current situation.
Also, we currently fertilize food crops with cow manure, which also carries pathogens. These pathogens could be also eliminated by composting too, but I don't think anyone does this. This is usually the cause of e-coli and salmonia outbreaks in the US.
You copyright it (free) and publish online with a copyleft license.
You would absolutely win in court without the patent. Just point to the publishing date on GitHub. Then you sue them for filing a blatantly fraudulent patent.
What's the license?
Edit: Ugh, it's licensed CC0 public domain. Assholes.
https://github.com/IRS-Public/direct-file/blob/main/LICENSE