May I have a look at this topic? Why does the answer say that it is a limited perspective and the third person is not an omniscient perspective?

The traditional third person is an omniscient perspective. Since the 20th century, people began to notice that the third person limited the perspective, because in the traditional third-person narrative, we are God, and we know everything that happened, including the truth of psychological activities and events. From the perspective of third-person limitation, we only know a story through third-person narration. We are bystanders, but we are not God, we are not omniscient, so we limit all the grasp of characters and stories, so the third person limits the perspective.