A person should have almost total authority over how their own mind develops, so once a modified-mind-clone exists, they should be free to be fine with being shut down (if that truly holds on reflection, which could just be ensured to be the case by stipulation, how thoroughly the modified-mind-clone needed to be modified in the first place). But it might be unethical to create them, especially if the original doesn’t endorse their creation.
A person should have almost total authority over how their own mind develops, so once a modified-mind-clone exists, they should be free to be fine with being shut down (if that truly holds on reflection, which could just be ensured to be the case by stipulation, how thoroughly the modified-mind-clone needed to be modified in the first place). But it might be unethical to create them, especially if the original doesn’t endorse their creation.