The complaint isn't that the new behaviour is not compliant with some standard. It is that the change is arbitrary and pointless. None of your links contain th

The complaint isn't that the new behaviour is not compliant with some standard. It is that the change is arbitrary and pointless. None of your links contain the text "resolve.conf". Nslookup is an end user diagnostic tool and would not be expected to conform to any standard, even if there was one.