For backwards compatibility, couldn't they just use half the shaders at twice the clock? Tegra X1 is 2B transistors, but the GPU is much smaller than that, for BC, if they can use half the shader count, it could be as small as 300M-500M transistors, when considering Tegra X1 is made on 20nm with a ~17M Transistors per mm, Samsung's 8nm is ~3x as dense, meaning they could fit ~6B transistors in the same space, even losing out on 500M transistors would still net them 3 times+ the performance jump thanks to "Ampere+" architecture (Orin uses much more internal cache and "Dane" is rumored to be a much smaller sister die). As for DLSS, MX570 will support it, and the even lower end Nvidia A2 with just 1280 shaders and 40 tensor cores should be capable of DLSS, so I'd expect Dane to have around half the shaders of MX570 to fit a similar power envelope of the original Switch, giving it 1024 shaders, 32 tensor cores and possibly 8 RT cores (again half of MX570).
Even if the clock was 1GHz when docked, the GPU would push 2TFLOPs Ampere"+" and offer DLSS, when in portable mode, I'd expect them to use 600MHz or so, pushing 1.2TFLOPs Ampere, which should match up well with PS4 even without DLSS, though considering the speed at which the tensor cores could process 720p, DLSS could be a very realistic option for portable mode, which would see it exceed Steam Deck in visual performance, as it could render the games at 480p-540p and use DLSS to reach 720p, the benefit here is AA is applied via DLSS and the smaller screen would help hide any imperfections of the image.
A78C would allow a huge jump in CPU performance over the current Switch's A57 cores at 1GHz, I'd expect a ~50% increase in clock and IPC is about 3 times more performant over A57, and A78C can be an 8 core cluster. That could offer as much as 10 times the performance of the CPU found in Switch (for gaming, as I'm counting 3 cores vs 7 cores here).
Lastly, Nintendo currently uses LPDDR4X in their Switch, but I'd expect them to use either LPDDR5 or LPDDR5X, which at 128bits is 102GB/s or ~133GB/s. Switch has 25.6GB/s, so the upgrade is again huge. This is based on GPU architecture 2 years old right now, and Dane which if real, started in late 2019 after Mariko and before Orin's announcement in December 2019, should be ready this year or next IMO.
This is mostly what I've come to after the last few years of speculation, I also don't think the die needs to be limited to ~120mm^2, as Wii U's GPU alone was ~160mm^2 and was built on a more expensive MCM solution. We should actually know if Dane is coming this calendar year around the end of April when Nintendo releases their earnings and announce projected hardware sales, they are expecting to sell 23M units this FY, but if next FY there is 25M+ well that would mean they have entirely different units with different chips in them. I fully expect Nintendo to treat a new model like this as a "4K" revision, there is also a lot of talk from Nintendo's leaders about pursuing cloud technology for game streaming, which could mean they are building a "Dane" powered network to run their first party titles that target Dane onto the current Switch units, I don't expect Nintendo to launch exclusive Dane software in a capacity exceeding New 3DS had, at least not for a couple years, when they could have their cloud ready. Ultimately they could sell you a Switch "2" game on your Switch and when you play it, it launches a cloud version of the game, but when you play it on a Switch 2, it runs locally, wouldn't matter if you had a digital or physical version of the game either, sort of the best hope for an everlasting platform and moving away from hardware that Iwata talked about originally, and solves the problem of maintaining the 100M+ owners they currently have, that the president of Nintendo just talked about in their Q&A.
