I've been doing it only for 3 or 4 years, and this 100% lines up with my experience. There are times when I haven't been consistent, and it always comes down to feeling that "I can't do a good job of it right now, maybe later..." and then I miss that day, and miss that week, etc.

I use the mobile app Pixels for journaling though. It lets the user define custom tags (I track emotions, activities, wake up time, body pains...), which for me is pretty useful, but I would say it also raises the floor on the effort it takes to make an entry, because I don't like to miss data points on those tags. So to the reader: start small, be forgiving, and don't worry about getting good data. 99% of the value of journaling is the practice.