Drupal 8 - Content entities - How __get (magical method) vs get (explicit method) work

core-lib-Drupal-Core-Entity-ContentEntityBase.php

<?php

  public function get($field_name) {
    if (!isset($this->fields[$field_name][$this->activeLangcode])) {
      return $this->getTranslatedField($field_name, $this->activeLangcode);
    }
    return $this->fields[$field_name][$this->activeLangcode];
  }

  public function &__get($name) {
    // If this is an entity field, handle it accordingly. We first check whether
    // a field object has been already created. If not, we create one.
    if (isset($this->fields[$name][$this->activeLangcode])) {
      return $this->fields[$name][$this->activeLangcode];
    }
    // Inline getFieldDefinition() to speed things up.
    if (!isset($this->fieldDefinitions)) {
      $this->getFieldDefinitions();
    }
    if (isset($this->fieldDefinitions[$name])) {
      $return = $this->getTranslatedField($name, $this->activeLangcode);
      return $return;
    }
    // Else directly read/write plain values. That way, non-field entity
    // properties can always be accessed directly.
    if (!isset($this->values[$name])) {
      $this->values[$name] = NULL;
    }
    return $this->values[$name];
  }