You're making comparisons with the lite and the OLED, two obvious stop gaps in the switch line. Having a very short marketing cycle for such minor upgrade (or even downgrade for the lite) makes sense.
It does not make much sense for a machine such as the one being discussed here.
The only statements we have from people that know about these dev kits (Nate, Mochizuki, Imran, others I might be forgetting) are that it's for 4K Switch titles, and that it's still another "Switch" model. These details are almost certainly
from their (likely independent) sources - ie. how these developers were using the hardware, and how they saw the hardware in 2021. If we assume all the above is true, they don't need ages to market the device. They may not need or care if the entire audience shifts over to the new device in any especially timely fashion, as Nintendo's own line up, as well as much (or all) of the early 3rd party line up will support the entire family of devices.
Nate did mention he knows of 3rd party titles exclusive to this device within the Switch family, but we don't know the timeframe. The existence of these limited exclusives does not preclude a short marketing cycle as well. The New Nintendo 3DS released with a 2 (?) month gap between announcement and release, and the "New" line of products ended up completely replacing the 3DS line in the long run.
The nature of this thread is bunch hardware enthusiasts discussing what's feasible - plenty of it admittedly way over my head - and often tailoring the discussion based on reputable rumours (see Nate, Bloomberg) or legitimate leaks (Nvidia NVN2). I can respect that the details in the NVN2 leak indicate a
very powerful device, but I think the sensible approach to things would be to reconcile this detail with the other reputable rumours we have, not just ignore the rumours entirely.
There's no evidence to suggest 2022 is possible. Team 2024
There's at least some insider comments and reports that point to late 2022 to early 2023. As far as I recall, there's zero evidence to suggest 2024. The only times I've seen that thrown out are some analysts and complete guesswork from folks like Grubb who admitted he had zero insight at this stage and is assuming we aren't getting any sort of revision. His last finger-in-the-air pitch was that we'd get an OLED Lite this year as a response to Furukawa's non-denial of new hardware, something Nate's at least implied he didn't agree with.