OSS Vanilla Spark is a versatile distributed query engine capable of handling various workloads but is generally slower than pure vectorized engines like Trino or Snowflake for OLAP tasks due to its hybrid processing model. While Spark's approach allows for flexibility in processing semi-structured data and complex queries, it lacks the optimization specific to columnar data formats. The article also discusses potential enhancements to transform Spark into a more vectorized engine through various extensions and solutions.