Definitely, the smartest thing to do. Leaving Durant to go 1v1 is the lesser of two evils. You trap Durant and there's the potential of Curry being open and you're fighting to stay afloat trying to match his 3-pt production. It's half the reason why they've been able to limit his scoring production in the last three Finals' because they force the ball outta his hands and make players like Draymond, Iggy etc etc take shots.
so you really believe this to be the lesser of two evils? Curry isn't a mismatch with whoever is guarding him, Durant is.
This sounds like Curry is the more dangerous player of the two if you believe you would be 'fighting to stay afloat' by letting Curry go one on one as compared to Durant.