Hmm, as one who has owned and sailed his own boat, I'd say it's fun, but I wouldn't equate it to freedom in any fundamental sense.

What sense of freedom that sailing brings, in my experience, comes from the permission one gives oneself, for a time, to do nothing else. "Today I'm going sailing, and to heck with (whatever)". It's good for gaining psychological distance from the daily concerns of job, family, or whatever that may cause us to feel tied down and not-free. So are a lot of other things. I, at least, was never able to experience sailing as more than a temporary respite. And it kinda stopped being fun when taking care of the sailboat and paying for its upkeep joined the list of daily concerns that had to be dealt with.

I go with Nate's assessment that freedom is related to control -- or the sense of control. It's about feeling that one has choices, and is beholden only to the consequences of what one has freely chosen. I suspect that that has been true forever, and has little to do with the service of our modern "energy slaves".