Nested ContentChildren have wrong content in Angular

[Jakob-em]

Describe the bug
When angular components/directives are nested and use the ContentChildren decorator the inner component/directive
has a reference to itself as part of contentChildren.

When the same code snippet is used in a new angular application the inner component/directive doesn't have a reference to itself. (as it would be expected)

To Reproduce
A reproduction can be found here

1. Open DevTools
2. Go to Basics / Component / With ContentChildren / Default
3. See that children: [ChildDirective] is logged

Expected behavior
The ChildDirective should not have any children and therefore log children: []

Code snippets

@Directive({
  selector: '[storybook-child]',
})
class ChildDirective implements AfterContentInit {
  @ContentChildren(ChildDirective)
  children: QueryList<ChildDirective>;

  ngAfterContentInit(): void {
    this.children.changes.subscribe((c) => console.log(c.toArray()));
    console.log('children:', this.children.toArray());
  }
}

@Component({
  selector: 'storybook-with-content-children',
  template: ` <div></div>`,
})
class ComponentWithContentChildren implements AfterContentInit {
  @ContentChildren(ChildDirective)
  children: QueryList<ChildDirective>;

  ngAfterContentInit(): void {
    console.log('parent:', this.children.toArray());
  }
}

System
System:
OS: macOS 11.2.3
CPU: (8) arm64 Apple M1
Binaries:
Node: 15.9.0 - ~/.nvm/versions/node/v15.9.0/bin/node
Yarn: 1.22.10 - ~/.nvm/versions/node/v15.9.0/bin/yarn
npm: 7.5.3 - ~/.nvm/versions/node/v15.9.0/bin/npm
Browsers:
Chrome: 89.0.4389.114
Safari: 14.0.3
npmPackages:
@storybook/eslint-config-storybook: ^2.4.0 => 2.4.0
@storybook/linter-config: ^2.5.0 => 2.5.0
@storybook/semver: ^7.3.2 => 7.3.2

Additional context
I would be happy to help out with this issue if somebody could give me any hints where to start.

[github-actions]

Automention: Hey @Marklb @MaximSagan @kroeder, you've been tagged! Can you give a hand here?

[Jakob-em]

After digging a bit more I found out that this was the default angular behaviour before Ivy: angular/angular#10098 (comment)

And because storybook is not using Ivy the behaviour is different than in a real angular app.
So it should be fixed with #13768