That's probably because Bill & Melinda issued their grants a few years back. You can see a list of all of the high-tech outhouse makers here [0]. Many of the designs are out in the field for long-term testing.
The Gates Foundation is not relevant here, in that problem field, in any meaningful way. It is an issue about operational structure and unit cost structure. Tax money gets spent on black Mercedes cars instead of what it is supposed to be spent on.
Also, it is not a technological issue at all. In terms of tech for sewage treatment, the path forward is clear. In terms of politics it is not.
But if Bill would like to phone me, then I would explain to him that while decency does score high in my books, you can have perfect golden toilets that dump sewage into rivers. In that case I would rather take a veldtie in the bushes.
I can find two. One from two years ago and one from six years ago.
https://hn.algolia.com/?q=open+defecation
If you search on toilet, there's a lot more articles that come up, but at first glance, most don't appear to be about solving open defecation, though there is one on the front page of the search about the Gates foundation funding toilet research.
https://hn.algolia.com/?dateRange=all&page=0&prefix=false&qu...
In contrast, you can put in antibiotic resistant and limit it to the past year and get pages of hits. Granted, they won't all be about the latest sexy research methods.
https://hn.algolia.com/?dateRange=pastYear&page=0&prefix=tru...
It has 159 comments, probably because of how it affects "first world wealthy people".