That's like saying we should make taxonomies in biology objective. But if we were to do that, we'd need to analyze the DNA and things like that. And in order to do that, we'd need an explanation of the Darwinian theory of evolution. We'd need to understand that all organisms have a common ancestor, and that things gradually evolved over time, and each species diverged at some point by the pressures of the environment.
And Socionics... doesn't have that kind of theory or an explanation that makes classification possible or "objective".