The correct knowledge about the reality you may take into account, what gives more possibility on better actions, or do not take.
> If they don't make your life better in one way or another
Then either the knowledge is incorrect (while there are more signes it's correct)
or you may to think and train better to get the use from this knowledge.
Jung types should help to take into account one of important psyche compatibility traits useful to make long pairs. This needs good enough typing skills, as people do many typing mistakes. Without such skills it's possibly to do a harm by a mistyping with significant chance.
There is indirect usefulness of Socionics - to point on the importance of personal sympathy and friendship feelings to choose your pair. Many people underesteemate soul attraction and positive emotional influence, what leads to short, surface and not good long relations.
It's partly possibly to evaluate friendship abbility directly without Jung types. To take into account Jung types is T approach, while there are 3 else functions. Jung types is not anything important for the compatibility and so general evaluation by other functions and logical processing of other factors is important too.