Why doesn't IANA operate a whois server? Why should they? What will it produce?
It will produce an authoritative source of information that automated systems can query and where those systems can reliably parse the output. In cases where a human needs to check unusual cases, there will be a complete explanation in the comments field of the whois output.
Why don't they publish a more detailled explanation field in each IANA allocation record so that they can explain the precise status of each block? Why should they?
In order to be authoritative one must be seen to be authoritative. When the information is not available, people are more likely to attribute this to incompetence than secrecy.
And why don't they do all this with some 21st century technology? Why doesn't vwl help by giving ARIN his changelog, if any?
Who is vwl and why should this mysterious person give their changelog to ARIN. Assuming that this represents changes to something, what is that something. --Michael Dillon