That whole article is BS, they even say it themselves:
Rates are rarely paid at a flat rate per stream
There is no payout per stream. Instead a fixed percentage of the subscription price is shared among each streamed song. So why does Tidal pay more then? Either their subscriber numbers are still incorrect (they have a history of publishing way higher numbers than in reality), their subscriber listen to less music (which is the main reason Apple Music pays more per stream on paper, since its often bundled) or their audience focuses more on a single artist (or a genre).