Conclusions about the ethics of who should be able to buy and use these devices will inform the way the business of supplying them works - effectively we need to decide the size of the potential market. Would it be people with Alzheimers? People with memory disorders? Anyone who can afford it? Would these devices be the equivalent of a prescribed medical procedure or an elective, 'cosmetic' surgery? If society as a collective group decides that the devices should be illegal to anyone without a valid medical reason (let's say we don't want children using them to 'cheat' in exams) then developing, or investing in, businesses to innovate in the area would change dramatically.
In essence, you can't easily put the genie back in the bottle, so it's better to decide what you're going to do with the genie before it's out.