Rumors about the so-called Nintendo Switch Pro mid-generation console refresh started spreading in early 2020, with the first information leak pointing to a custom processor based on NVIDIA's Volta architecture. Later in 2020, Bloomberg sources revealed that the Nintendo Switch Pro could feature 4K resolution support and appropriately increased computing power.
From that point onwards, rumors got even wilder. In 2021, reports mentioned improved handheld mode and NVIDIA DLSS support; the possibility of improving the resolution and performance of older games; a bigger dock with an Ethernet port and two USB 3.0 ports; and so forth. Nintendo didn't make any announcements, though, leaving fans speculating for a long time. A Chinese Switch accessories manufacturer reignited hopes for a Nintendo Switch Pro to land in 2022, but that obviously never happened either.
As the saying goes, though, there's no smoke without fire. In the latest episode of the Digital Foundry podcast, John Linneman reported that the Switch Pro was indeed a real project. However, Nintendo ultimately decided against launching the console.
I think at one point internally, from what I can understand from talking to different developers, is that there was some sort of mid-generation Switch update planned at one point, and that seems to be no longer happening. And thus, it's pretty clear that whatever they do next is going to be the actual next-generation hardware.
He later added that Nintendo would be doing a proper Switch successor instead, likely for a 2024 release instead of 2023, though this part is just a prediction. This lines up with the most recent rumors of an NVIDIA Tegra239 SoC being prepared with an eight-core CPU, NVIDIA DLSS, and ray tracing support pointing to a Nintendo Switch 2 rather than a mere Switch Pro.
However, it also means that the new Switch won't launch alongside The Legend of Zelda: Tears of the Kingdom, currently scheduled to be released on May 12th, 2023. Nintendo aficionados were hoping for a repeat of The Legend of Zelda: Breath of the Wild, which launched simultaneously as a cross-generation title on Nintendo WiiU and Nintendo Switch in March 2017.
Of course, there's also a chance of The Legend of Zelda: Tears of the Kingdom getting delayed into 2024, but it's one that Nintendo fans aren't prepared to entertain right now.