Not necessarily. It's true if the person making the decision is getting paid directly from the mining. But perverse incentives abound in the cryptocurrency space. For example, consider Celsius:
As they thrash around in bankruptcy, they have proposed that they will mine their way out of the hole. Will this work? I doubt it. But will it let the CEO stay in charge for a while longer, taking in more investor money and continuing to get paid? Possibly! So actual economic efficiency may not matter.
https://amycastor.com/2022/09/11/crypto-collapse-celsius-voy...
https://davidgerard.co.uk/blockchain/2022/08/11/crypto-colla...
As they thrash around in bankruptcy, they have proposed that they will mine their way out of the hole. Will this work? I doubt it. But will it let the CEO stay in charge for a while longer, taking in more investor money and continuing to get paid? Possibly! So actual economic efficiency may not matter.