why not the eight season on TV?

Some TV shows just run their course and go out on a high. I really thought the show ended a few seasons back. Ending Buffy's life in "The Gift" but she was brought back to life!!!
I have read the graphic novels and liked them, but I think if they tried to do the show back on TV most of the people who played the characters wouldn't return. Because they're grown up and doing other shows now and Buffy wouldn't be the same!!!
Believe me I miss the show big time and don't want to see it with others doing our favorite players!!!
But Buffy season eight # 1 was great!!!