Why is API Key authentication generally considered less secure than JWT for client-side identification if the key is stored directly in the client application?

API Key authentication, when the key is stored directly in the client application, is generally less secure than JWT for client-side identification primarily due to the static, unexpiring, and easily extractable nature of API keys, and the lack of inherent integrity and user-specific controls. An API Key is typically a long, secret string used to identify the client application to an API server, granting it access to resources. When this key is stored directly within the client application's code (e.g., a mobile app's binary, a web application's JavaScript bundle), it becomes susceptible to extraction through reverse engineering or simple inspection. Once stolen, such an API key usually grants indefinite access to the resources it is authorized for because API keys rarely have a built-in expiration mechanism. This means a compromised key remains valid until manually revoked, providing a persistent attack vector. Furthermore, API keys ofte....