Given his talents, I think it depends on getting Anthony Davis. If that happens, the potential is there for a championship level collaboration.
Otherwise,I think we'd be better positioned for a potential championship going forward if we let him walk. He's a point guard, he's not an MVP candidate and he isn't someone who makes everyone around him better. Its not that he isn't great, but you won't win a title if he's your best player. Without an even better player like AD, I wouldn't want to pay him.
Tatum Brown and Hayward all will need the space to expand their game next year. I think the team would be better long term built around them, and that won't ever happen with Kyrie here.