I haven't. I registered on ghost two years ago before turning 40 and have been paying them for two years now while I write nothing. It's hard to get started. I'm hoping to overcome this. This post helps.
I'm a bit eccentric in this respect as I journal more than most people. I have subject matter journals that I use. When I'm working on graphics, I write in my graphics programming journal. When I'm working through abstract algebra, I write in my maths journal(s).
I do some times come across ideas for longer-form essays. But it's usually from the accumulation of small ideas, thoughts, feelings, and the like that I find them.
Eventually, blog posts.
However if it's the anxiety of performing for others that overwhelms you, try developing the habit of writing in private. You can conquer those anxieties later when you're more confident in your underlying skills.
It’s OK to blog about silly things. Rant about something that annoyed you. Talk about how you made something. It doesn’t have to be perfect. No one cares if you make mistakes. Going from zero to something is the important part, not going from something to perfection.
And the more you do all the, the sooner you’ll find your own voice, and the easier it all gets.