That was a coincidence.
Niels Bohr once said: "Prediction is very difficult, especially if it's about the future.". And that was what Mercurian's post was about.
Back then, there were plenty of indicators on Weibo and elsewhere pointing to a November 2019 launch. For me, the 4TB delay was further confirmation.
Don't want to toot my own horn, but if you look back at the 16" MacBook Pro delivery dates with 4TB, they were shipped almost exactly 5-6 weeks after my post. The Apple Store estimates were right on the dot.