All very well and good...
Very noble, a good cause I do agree with. The issue is that the end goal is rather unrealistic. Why? A lot of the problems are also cultural.
For example; digging your own "shitpit" (i forget the formal name) or filling in an existing one (generally just handling your own excrement) is seen as beneath people in India, and to be known to do so could brand you as an untouchable, the lowest caste in indian society. There's an increase in India of people wanting to build overly huge pits that are going to last for multiple decades of use just so they never have to get involved with excrement maintenance. Not only this, but in India open defecation is seen as the norm. Attempts to introduce toilets to indian villages have lead to varied responses, included the toilet becoming a shrine or being used to make curries.
Likewise, there are areas of Africa where the floors are absolutely littered with literal human excrement and other waste; there are beaches absolutely filled to the brim with human faeces and polluting the ocean. Again, there is the issue of open defecation being the norm, but there's also clearly a cultural component here as well; there's no centralised giant pile of rubbish, its largely dropped as its used.
In china as well, open defecation is a reality for millions and millions.
The (seemingly insurmountable) challenge isn't just more efficient methods of waste disposal, but in changing long held cultural beliefs around the handling of excrement and how people are supposed to defecate.