Contango and Backwardation

So I’m aware

Contango: Forward > Spot

Backwardation: Forward< Spot

Normal Contango: Forward > Expected Spot

Normal Backwardation: Forward < Expected Spot

I came across something saying normal contango is a biased predictor of expected spot rates. Does that mean normal backwardation is also biased and regular contango and backwardation are unbiased?

Also is Contango always associated with speculation normal and regular and backwardation associated with hedging normal and regular?

Please help