You wrote :
„My opinion, for what it is worth:
*) we should not be concocting our own norms or definitions or criteria, but only follow those that are in place, from sources of authority“

It is a fact that OSM has a definite opinion about place mapping (see the wiki). So we do not have to follow exactly the definitions of authorities in a country. It is more important that the place mapping wordwide is similiar in OSM. Of course every country can look for a reasonable, additional rules.

You wrote :
„*) even if we were to set up our own definitions, they should be practical and politically tenable. Definitions based on people’s gender are quite unacceptable, these days, for one example.“

See my last post : My proposal comes in Rajasthan to quite similiar results as census 2011. There are only 12 census towns of 297 towns, where census comes to a different result. In the other cases (16 places) the census decisions are completely wrong, I think. And it is a bit strange to declare a place with population > 10000 as a village.

You wrote:
„If we do have to define a “town” for ourselves, even if I do not like the idea at all, important criteria should be the availability of services, such as schools of various levels, hospital, transportation infrastructure, hospitals.“

As far as I can see, the headquarters of subdistricts are the places with the infrastructure you mention. The progress of the India map in OSM is remarkable in the last years. But still the number of mappers with very good mapping practise is still small.
An example: While mapping subdistricts I saw hundreds of place nodes which were imported 12 years ago by AND. But often nobody looked for the position errors (up to 50km!), nobody mapped the exact population and the imported nodes are completely untouched.
That means, we need a practicable and reasonable rule what is a town and what is a village.
When the census 2021 is done, we have reliable data to correct the census towns (if wanted) and that is an easy task.

You wrote :
„My preference would be to only publish what is beyond discussion:

  • this is an inhabited place
  • its name is xxx
  • population=9999 , if possible with a source reference and a date“

That is not possible. If you want to map the name and the population of a place, you have to put a place tag and also decide whether it is a hamlet, village,…… city. Then you can add name and population.
By the way as far as I know, nobody added a date-tag to the population. Nevertheless that is a really usefull information.