I agree with your general assessment re: experience, but I wish people would stop talking about these sorts of things in years and months. I understand why it's difficult to express it in hours, but even a very rough estimate of total hours spent is a far, far more useful metric than "years".
My personal experience with studying Japanese has been that there's roughly two camps of people: those who become fluent-ish in 1-2 years, and those who know ~100 kanji after 3 years (1-2k for fluency). The primary difference between these two camps is that the former studies 6-8 hours a day, and the latter has Japanese classes thrice a week, that's it.
Speaking in hundreds, thousands or tens of thousands of hours gives you a much better idea of what's actually necessary to make the magic happen, and makes it easier to judge how well you're doing: is making barely any progress in 1 week a bad thing, or a really bad thing? That depends on whether a week translates to 3 hours or 50 hours.