“Correlation is not causation.”
It is amazing how many people will throw that out over number crunching such as this. Sometimes, correlation reveals causation. That is mostly how doctors diagnose sickness. It is called symptoms.
In science, the only time that correlation comes close to being causation is when there is a dosage related curve that reflects a stronger correlation.
What you say is true about correlation providing clues. That is why AI is so beneficial in medicine as it is more comprehensive in differential diagnosis.