...is by being able to choose how you want to live your day, every day.
Retiring early gives you an immensely powerful thing called "options" and "choices", and depending on your level of maturity and take on life - it can be very daunting (fear) or very exciting (faith).
Why some people see it as feared and daunting is because they're so used to have a fixed regimen where someone else had already dictated to them as to how to live their lives:
Do this until retirement, then play a bit more, and then die.
Trouble is, this has become the default program for many, and these people may not be ready for options and freedom.
In fact, I recommend it, because we thrive on social interactions, routine etc. Just that when you're financially free, you tend to have less fear and can be more creative and vocal about doing good work, rather than fearing to say what you think, which may not be a good thing.
For those who have other dreams, such as to travel the world, start a business, slow down to spend time with loved ones, watch your children grow up, do volunteer work - that's all optional for you, once your finances are automated with passive income coming in regularly at slated timelines.
In a nutshell, financial freedom is more about the freedom of choices it brings to your mind, heart and lifestyle, more than anything else.