Newer AWS Glue versions—such as Glue 5.0—include significant performance optimizations for **Python-based** ETL jobs, often reducing runtime by 10–60%. These improvements do not require any code changes, making version upgrades a simple and impactful optimization. When jobs remain on older runtimes such as Glue 3.0 or 4.0, they execute more slowly, consume more DPUs, and incur unnecessary cost. Additionally, Glue 5.0 offers more worker types (larger standard workers and memory-optimized workers), that can provide additional performance gain for some jobs. This inefficiency does not apply to Scala-based jobs, which do not benefit from the same performance uplift.