I have been journaling daily for close to 20 years, with the exception of a few breaks and skipping journaling in really busy days.
From my personal anecdotal perspective I feel that overall it's a positive experience. I've tried multiple mediums, Evernote, Workflowy, Pen & Paper, Google Docs, and countless of journaling apps. I find pen and paper the best, probably because I can parse my thoughts better when I write them down over typing them. Even though typing is much faster. There is something magical about making a moment for yourself with a fresh cup of coffee, some music, a pen and a journal.
I've also experimented with the type of content I want to journal. It feels like the standard is to write about your day. I find that the least fun way to journal. Albeit at times my personal day to day life bleeds into my journaling, I prefer writing about my thoughts, what I'm struggling with, debating to do, what I'm trying to improve.
Essentially for me, journaling serves as part self-therapy, part life strategy writing, part goal planning and blocker removal strategies. I can analyze my actions and their side-effects. Do it long enough and you start seeing patterns in your way of thinking, or you will catch yourself writing about the same thing yet again. I strongly suggest you don't just write when you journal, create flowcharts, make bullet lists, underline things that you think are important. It's a very undervalued thinking tool.
Usually when I talk to friends about journaling the common deflection is "I don't have that kind of time". Here is the thing, it's ok to write just one paragraph. Sometimes even a single sentence. I have journal entries that just say something like "I have nothing to talk about". The thing is you are building a habit. Most of my journal entries are about 2-3 paragraphs, about 10 minutes of writing. Occasionally if I feel overwhelmed, or troubled by something I might write for an hour. Other times I might write a short journal entry and 12 hours later make an update with new thoughts.
I hope this helps someone thinking about journaling.
To echo the linked article, what's interesting is reading past entries and realizing how you are often wrong, but tenacious, stubborn, a dreamer, someone that doesn't give up...because you are still doing it...you are still here, fighting.