This news is actually a little hard to interpret.
To quote the article: " The amount will now be diversified into corporate assets "
Japan's central bank does bailouts of the capitalist class by purchasing stock. It owns 4.7% of all public stock in all of Japan.
https://www.bloomberg.com/news/articles/2020-12-06/boj-becomes-biggest-japan-stock-owner-with-434-billion-hoard
So this may not be them moving toward abandoning the dollar (the watcher.guru article mentions that they are selling US and EU bonds but no percentages).