Swift Concurrency - SWIFT​_​DEFAULT​_​ACTOR​_​ISOLATION

If SWIFT​\_​DEFAULT​\_​ACTOR​\_​ISOLATION is turned on in your project with swift 6(xcodeVersion 26.4), does it mean the following struct is Main actor isolated :

struct TokenResponse: Decodable {     let expiredIn: Int     let accessToken: String     let tokenType: String }

I thought yes.However when I checked my answer using claude and gemini, they both say NO. However chatgpt and copilot say YES. Now I dont trust AI anymore.

Would be appreciated if you can clarify on this. Thanks!