Fantastic analysis, and well presented.
It makes sense that 53% of accounts haven't bothered to post a single thing, given the disconnect between "account requested" and "account created".
Most people would forget, or get an obscure password, and never come back.
I wonder also how many accounts are "lost"; and are those that will never have any activity on the chain again, due to loss of passwords or keys.
I too wonder how many accounts are lost. And I would think it is a lot