No, there is no 4K Nintendo Switch in the making.
I for one remain puzzled as to why human beings consider these reports as news.
NintendObs Daily. Thursday, September 30.
"A news report on Sept. 30, 2021 (JST) falsely claims that Nintendo is supplying tools to drive game development for a Nintendo Switch with 4K support. To ensure correct understanding among our investors and customers, we want to clarify that this report is not true." — Nintendo Co. Ltd. This should quell the rumors, but obviously it won't. I for one remain puzzled as to why human beings consider these reports as news. Nintendo very rarely responds to faulty claims by videogame media and the news media at large, but when they do, that means they've really quantified the impact and insured that an intervention was necessary. As is the case here since Nintendo Switch (OLED model) is launching in just about a week, something Nintendo also made sure to remind people of in the tweet right after saying: "We also want to restate that, as we announced in July, we have no plans for any new model other than Nintendo Switch - OLED Model, which will launch on October 8, 2021."