Class B inherit Class A that adopt ObservableObject, @Published do not work?

Hi, guys.
if I declared Class B inherit Class A that adopt ObservableObject, Class B has a @Published property, SwiftUI View not updating when the viewModel’s value changes? Is that a bug or something else?
Isn't it the same issue announced as Resolved in iOS & iPadOS 14.5 beta 2?

iOS & iPadOS 14.5 Beta 6 Release Notes

Updates in iOS & iPadOS 14.5 Beta 2


Combine

Resolved in iOS & iPadOS 14.5 Beta 2

Using Published in a subclass of a type conforming to ObservableObject now correctly publishes changes. (71816443)
Class B inherit Class A that adopt ObservableObject, @Published do not work?
 
 
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