Dependency management is one thing Docker handles, and I don't really think it does a great job of that. To me containers solve the challenge of getting a development environment that closely matches production. It standardizes how deployments are performed, how testing environments are set up. Before this we had complex, immutable ansible scripts, READMEs, install scripts that had to be babysat, snowflake servers that no-one knew how they were configured. It's also an extremely widely used technology, so if you use it in your stack you can expect many people you hire to know how to use it from day one versus everyone learning a bespoke set of custom scripts.