That’s assuming a developer owns all the codebases they work on. Many don’t, because they work for an employer with a large team and a large existing codebase.

That’s assuming a developer owns all the codebases they work on. Many don’t, because they work for an employer with a large team and a large existing codebase. If the language evolves and the project manager is 100% keen on adopting new features then it’s going to affect everyone on the team.