Что я тут получаю?

class User extends Model
{
    private $session_uid;
    private $uid;
    
    public function __construct($uid = null)
    {
        parent::__construct();
        $this->session_uid = $_SESSION['uid'] ?? null;
        $this->uid = $uid ?? $this->session_uid;
    }
 
    public function getUser()
    {
        return $this->pdo('select * from users where id = ? limit 1', [
            $this->uid
        ])->fetchObject(__CLASS__);
    }
}
 
class Main extends Model
{
    public $user;
 
    public function __construct()
    {
        parent::__construct();
        $mOdj = new User();
        $this->user = $mOdj->getUser();
    }
}

$main = new Main();
echo '<pre>';
print_r($main);
echo '</pre>';

class Main
{
.....
public function user($prop)
{
return $this->user->$prop;
}
}

$user = new User(12);
echo $user->id;

class User extends Model
{
    public function getUser()
    {
        return $this->pdo('select * from users where id = ? limit 1', [
            1
        ])->fetchObject(__CLASS__);
    }
 
    public function test()
    {
        return $this->id;
    }
}
 
class Main extends Model
{
    public $user;
 
    public function __construct()
    {
        parent::__construct();
        $mOdj = new User();
        $this->user = $mOdj->getUser();
        echo $this->user->test(); // Что мы тут имеем?
        }
}

class User extends Model
{
    protected $session_uid;
    protected $uid;
    protected $config = null;
    public function __construct($uid = null)
    {
        parent::__construct();
        $this->session_uid = $_SESSION['uid'] ?? null;
        $this->uid = $uid ?? $this->session_uid;
        return $this->getUser();
    } 
    protected function getUser()
    {
        // метод pdo у вас где-то определен
        $this->config = $this->pdo('select * from users where id = ? limit 1', 
            [$this->uid])->fetchObject(__CLASS__);
        return true;
    }
    public function __get($prop)
    {
          return property_exists($this->config->$prop) ? $this->config->$prop : null;
    }
}

$user = new User(12);
echo $user->id;

class User extends Model
{
    protected $session_uid;
    protected $uid;
    protected $config = [];
    public function __construct($uid = null)
    {
        parent::__construct();
        $this->session_uid = $_SESSION['uid'] ?? null;
        $this->uid = $uid ?? $this->session_uid;
        return $this->getUser();
    } 
    protected function getUser()
    {
        // метод pdo у вас где-то определен
        $this->config = $this->pdo('select * from users where id = ? limit 1', 
            [$this->uid])->fetch(PDO::FETCH_ASSOC);
        return true;
    }
    public function __get($prop)
    {
          return isset($this->config[$prop]) ? $this->config[$prop] : null;
    }
}