translateEquality of IndexBounds aims to save work by re-using the existing _backingBSON from the corresponding MatchExpression.

By making _backingBSON optional, translateEquality must ensure that the provided bson object is not only valid but also holds a value.

With the most recent patch, this functionality is done using a boost::optional. However, boost::optional may incur performance penalty compared to a simpler bool/value solution.

This ticket aims to investigate the performance impact of boost::optional on this function call and update the implementation accordingly.