HarmonyOS @ObjectLink 渲染组件更新同步问题

代码片段如下：

@Observed
class ClassA {
  label: string = "1"

  constructor(label: string) {
    this.label = label
  }
}

@Observed
class ClassB {
  public a: ClassA;
  label: string = "1"

  constructor(a: ClassA, label: string) {
    this.a = a;
    this.label = label
  }
}

@Component
struct ViewA {
  label: string = 'date';
  @ObjectLink
  b: ClassB

  build() {
    Column() {
      Text(this.b.a.label)
      Blank().height(20)
      Button(`更改a.label`)
        .onClick(() => {
          this.b.a.label = "更改后的值"
        })
      ViewC({ a: this.b.a })
    }
  }
}


@Component
struct ViewC {
  label: string = 'date';
  @ObjectLink
  a: ClassA

  build() {
    Column() {
      Text(this.a.label)
      Blank().height(20)
    }
  }
}

@Component
export struct ViewB {
  @State b: ClassB = new ClassB(new ClassA('原始值'), "b_label");

  build() {
    Column() {
      Text(this.b.a.label)
      Blank().height(20)
      ViewA({ label: 'a_label', b: this.b })
    }
  }
}

点击ViewA button ，更改this.b.a.label = "更改后的值"，只有ViewC的Text文本渲染生效，而ViewA，ViewB 的Text(this.b.a.label) 并不能更新生效，这是为什么呢