Whether Quartz is respected of not... the statement "too good to be true" is an opinion. That article is an opinion piece.
Objectively speaking, the economic data in 2019, almost any measure, was amazingly good. Unemployment was down. Real wages were up. Productivity was up. Trade was good. These are objective facts... where "objective" means they are measured the same way no matter which administration is in the White House so you can compare them.
When numbers that good happened during the Clinton administration, the political left hailed them as vindication.
My opinion is that presidents in general get too much credit for a good economy, and take too much blame for a bad one. But that is just right.
Ignoring objective economic data just because someone you don't like is in the White House is silly.