In any case: As long as any of the augmentation we're discussing here is strictly optional, then I have no problem with it. It's only if it starts getting forced onto the general population that there'd be cause for concern.
There's optional and then there's "optional." We already have a digital divide in which people without Internet access have fewer opportunities and dimmer prospects in life than those who have such access. If and when augmentation of human beings goes mainstream, we'll see that problem exacerbate. Yes, people will have the "choice" not to participate--but like those excluded from the digital realm today, they will face severe impediments to functioning within the rest of society. Some may prefer this, self-styled separatists. But others will be stuck in that situation due to economics and public policy.