I've also been disappointed with debug containers. They are often not useful for debugging trick production-only issues because so many of those issues are related to container state, which can be (often is) different inside the container. Certain languages/platforms and developer discipline are better about this than others, like if you're using functional/immutable languages then it's less of an issue.

For applications that aren't super high security, I've been really appreciating using immutable hosts (that get regularly updated/rotated), along with CI/CD that is constantly rebuilding from source, applying latest software updates, and deploying the latest version of the app. Combined with other tools like scanners, and de-bloating your images, it really raises the height of the fruit.