I've spent a lot of time unemployed and employed. When I have a job, I think like you do, and wish I could chase my own dreams and passions. When I have no job... I just sit around. For weeks/months, doing nothing. Sometimes I take small steps towards a goal I have, but mostly they turn out to be a lot more difficult or tedious than I expected.
"Do what you love and you'll never work a day in your life" is nice to hear, but the flip side of it is "No matter what you do, it's work."
I've found the quote, "If you want to learn to hate something you love to do, try earning a living at it" more apt in the real world.
I think the modern economy has sucked the satisfaction part out of pretty much every job that exists. Corporations control basically everything now, and have squeezed out small businesses, and I'll simply point to the movie "Office Space" to show how soul-sucking they are. Government bureaucracy is soul-sucking as well (speaking form personal experience).
I have grown to see that debt is the new modern chains of slavery - not as brutally oppressive, but more elegantly designed, as a person is more motivated and will work harder if they
believe they are working for themselves. That allows the elite to harvest more wealth off their backs, more efficiently. So it is essential to stay out of debt.
I attempted to sidestep this by becoming a public servant, and seeing if I could derive satisfaction out of serving my fellow citizens, but that hasn't really worked. My work is too abstract, too removed from the front lines, and here in Canada we just endured a decade of Harper and his complete disdain for us - on me, it took an emotional toll.
Concerning freedom, absolutely. To me, pursuing FIRE is about purchasing my freedom from drudgery and this empty rat race. Unfortunately, every so often I need a little short-term pick me up and end up going on a small consumerism rampage, setting me back. However, I've read so many inspiring stories of people who retired early, and their life became renewed with purpose and excitement. I look forward to this as well.
Back to your original question, though - for me, this path is locked in because I have a young family, and their needs and security are overtaking my own right now. We need to be in a certain location, with a house, etc. So I must pursue FI in a not-so-radical way, but if I were single, my life would be very different - think living in a tiny cottage by a river.