> If you think your codebase is your competitive advantage or trade secret, you're in for bad time.

Obviously most developers know better, but you know who doesn't care what you think? The owner(s) of the business, and various other stakeholders. Try explaining this concept to them, and see if they get it :)

The people who work in codebases that are tightly guarded aren't guarded because the developers say so, of course.