Paywall so I found a similar article https://www.zerohedge.com/news/2019-03-07/brookings-says-chinas-economy-12-smaller-official-data-show

From the paper that the article cites:

our best estimate is that the true growth rate of GDP is probably overstated by almost 2 percentage points from 2010 to 2016

I mean, probably overstating GDP growth by average of 2 percent doesn't seem like compelling evidence for completely disregarding China's GDP numbers.

Link to paper: https://www.brookings.edu/wp-content/uploads/2019/03/ChenEtAl_web.pdf