I like your opinion in this case, and it is certainly very interesting, I just feel I should point out some of the absolutes involved and offer a somewhat different, though not entirely contradictory, perspective.

To quote Cat Stevens, ". . .there's a million ways to be, you know that there are."

The part that I agree with you is that people cannot be themselves when someone does not respect their own individual needs and desires and stuff. If I want cocoa puffs in the morning but my wife forces me to eat captain crunch, how can I thrive in my cocoa-puff lovin' lifestyle?

Where you say that one must allow, if not ensure, separateness, I would just like to point out that there is a big difference between 2 people allowing each other to do their own thing, if they so choose, and two people mutually agreeing in a totally-voluntary way to sort of meet in the middle and give up their individuality and/or privacy insomuch as they desire to do so. Like Cat Stevens says, if that is there way of being, it's not necessarily worse than maintaining totally discrete and separate selves.

For example, while I may not want captain crunch forced upon me, my love and admiration of my spouse as well as my desire to understand what makes her tick might lead me to curiously inquire about and to try to understand, voluntarily, the greatness of captain crunch. I may choose to eat captain crunch and learn to like it.

In this way, people can learn to share with each other completely and with mutual respect. If privacy is not desired, why is privacy vital if both partners share a desire to understand and to try out the other's likes and dislikes and sort of meet in the middle as a unified couple?

Anyways, like I said, you are entitled to your opinion and I do agree with it, only I disagree with you framing your recommendation as an absolute in light of the variations in people's preferences.