So you're saying as a result of these two positions that he holds he cannot possibly be wrong and I should blindly trust anything he says so long as he shows some workings?
I'm saying that you shouldn't dismiss what he's saying because he posted it on Twitter and/or because (you feel that) people are bashing the government.
He's a journalist at a well-respected newspaper, who has practical and academic experience using and interpreting data for his journalism, communicating his story in accessible way (both accessible in a pedagogical way and because the FT has a paywall). Engage with what he's posted and evaluate it on its merits, not just dismissing it because it's a Twitter thread containing a viewpoint that you don't want to be true.
Reputation isn't everything. But it's a useful guide.
Show me the data.