I've recently seen some teams claim to use third-party AI assistants like Claude or ChatGPT for coding. Don't they consider it a problem to feed their proprietary commercial code into the services of these third-party companies?

If you feed the most critical parts of your project to an AI, wouldn't that introduce security vulnerabilities? The AI would then have an in-depth understanding of your project's core architecture. Consequently, couldn't other AI users potentially gain easy access to these underlying details and breach your security defenses?

Furthermore, couldn't other users then easily copy your code without any attribution, making it seem no different from open-source software?