No two cases are exactly similar.
Not exactly, no. But some are close enough that judges can rely on Res Judicata or Collateral Estoppel to rule, saying that the case has already been determined by a previous case.
That is why plaintiffs, defendants and judges use hundreds of case laws to decide a specific case.
Haha...this is not true. Name me a single case were "hundreds" of case laws were used to decide the case. Usually there are 3-4 precedents used.
Historical rulings should be used to understand the laws, but should never be used as binding to decide the cases.
Your opinion is irrelevant. Stare Decisis is a WELL established practice that has existed before this country was even founded.
This is where legal system is failing.
The legal system has ALWAYS worked this way since the American Legal system was founded. So you are wrong.