Isn't harry potter like Highlander?

i mean seriously, in the last movie voldemort says that only he can live forever, but he hasnt killed harry for the past 7 fricking books!!! i think it's like highlander, where there can only be one in the end. so jk rowling has made multi billions over a little copy of highlander!!! which is exactly why i wanna be an author lol, but if you think about it for a while... my point is correct haha