Except that Nintendo said that Switch sales were at 10 million on December 12th. https://www.nintendo.com/whatsnew/detail/nintendo-switch-sells-10-million-worldwide If Forbes and the WS Journal (owned by Fox News) are to be believed Nintendo magically sold 4 million more units for the remainder of December. Sorry but I'll take the more reliable source, Nintendo itself.
The Forbes, and WS Journal articles are nothing more than speculative clickbait, that ignore what Nintendo has already said.
Nintendo's announcement refered to sell-through, the analyst quoted in WSJ talks about shipments. December sell-through for Switch easily adds up to over 3m units, add units that are on store shelves and in transit, and then a shipment number that exceeds the Wii U's 13.56m isn't farfetched at all. You can argue that Switch shipments might be at 13.6m, 14.0m, 14.6m or whatever you believe the value to be at, but the premise of the article will remain true.