"Regardless of how this will be spun in J.W land, the reason can only be a coverup of poor statistics, instead of having to show a poor yearly report, they can now say we no longer collect the data."
This is a good point. It's a standard tactic of governments and other corporations around the world, too. Deliberately stop collecting data on subjects you find 'awkward' or you want to ignore, then if anyone challenges you, you can just claim "we don't know and can't comment on that as we don't have the data".
It's a trick, for example, that the UK government have started using now that they have reduced the amount of data they collect about ethnicity in the UK population census, so that there is plausible deniability over concerns about mass immigration. Up until a number of years ago, the census used to collect very specific information on how people identified themselves (racial/ethnic background, etc) and the resulting nationwide stats were available to see and download from the GOV.UK website. But now, they've reduced the amount of info they collect about ethnic background, to obfuscate the scale of immigration in British towns and cities.
It seems the org is doing something similar to avoid having to confront the degree of visible decline in the house-to-house work and other forms of ministry. If you don't have the numbers in the first place, then there's no hard evidence of a problem for you to have to explain to critics!