Javascript – Im getting 'TypeError: Cannot read properties of undefined (reading 'owner')' because component hasnt loaded an observable yet

Although the app works fine despite the error, I am receiving that error in my console because my component has not loaded the ‘post’ observable from the backend through the postService. My code is:

Component

export class PostComponent {
  post!: Post;

  constructor(
    activatedRoute: ActivatedRoute,
    private postService: PostService,
    private timeFormatService: TimeFormatService
  ) {
    activatedRoute.params.subscribe((params) => {
      if (params['id'])
        postService.getPostById(params['id']).subscribe((serverPost) => {
          this.post = serverPost;
        });
    });
  }
}

My html just displays post values such as {{post.owner}} or {{post.title}} in paragraphs or headings.

Im getting that error for each post value.
Ive figured i can fix this error by setting default values by changing post!:Post; to:

post:Post = {owner: '', title: ''}

And when the postService gets the real post details from the backend it updates the values. Im sort of new to coding, is this the correct way to do it?