Yes. He's a better centre forward than the alternative, Beto. The Derby MOTM performance vs Liverpool - just a few of them which I don't think Beto could come close to a season makes the difference.
If we sell Calvert-Lewin for £12m, and start Beto tomorrow an he gets a knock - we wouldn't have an actual centre forward.
If we can get a decent fee/player swap then I understand the gamble, but we can't get worse in the final third and whatever your opinion of him - losing him for £12m without any replacement is us getting worse.