The obvious answer is that T239 is both chips. It likely was 8nm (with power draw problems) around the time Brainchild talked about the chip having power issues... That was Spring last year (so before that, we are talking a midgen refresh probably being canceled at the end of 2020. Then the T239 chip shrunk, giving us the DLSS test results sometime after June 2021 that LiC posted in here last week. We know engineering samples were in the wild in April 2022, that gives them plenty of time to cancel production on 8nm, redesign it for 5nm and have it launch in 1H 2023. Remember Zelda was delayed at the end of March 2022 (around the time engineering samples for T239 exist) to May 2023, that is probably because Drake was finally free of power issues. We know as of August 2022, that T239 is ready for full production, and thus all components for a next generation Switch is ready for production, lining up nicely for a 1H launch of Switch "2".
This is just the possible timeline of what happened, I think this makes perfect sense thanks to the OLED model, which Nintendo was already on the hook for these components. So if DF is correct about a midgen refresh in the past being canceled, I think it's clear why Switch "Pro" has hung around every year in the rumor mill.
October 2016, before the official reveal, that foxconn leak about the higher clocks and also a chip twice as big as TX1, and being confirmed by the content of the post like shape of the heat sink and it's size, the weight of the device, joycons, the naming of SL and SR buttons on the side of the joycons that slide into the rail system, literally a dozen other pieces of information that all checked out, and some reporting about Nintendo possibly moving to Pascal over Maxwell... Led to Switch pro rumors in 2016 before Switch even released.
In 2019, Nintendo overclocked Mariko to 1267MHz on the GPU, a higher CPU clock and LPDDR4X ram, giving about a 2/3rds performance jump, but ultimately retained Switch clocks, likely because of Switch's success and simplifying development. These clocks still exist in firmware.
in 2020 we get reports about Nintendo asking developers to prepare 4K versions of Switch games.
in 2021, we get brainchild's info, and news about a more powerful switch, also Switch OLED model launches with all new hardware, tons of changes, except to the main SoC. Why? I mean some of these components are just more expensive for no reason.
Nvidia hack on March 1st 2022 confirms T239, NVN2. End of March 2022, Zelda is delayed to May 2023, outside of the holiday season. April 2022 engineer samples for T239 exist. August 2022, T239 goes into production. November 2022 Zelda has gone gold, yet we aren't playing it.
That isn't even the entire history here, but everything is ready for a Switch "2" to be produced and released in the first half of next year, Zelda could have been shipped this year IMO, delaying it for what reason is hard to tell, it's not like Nintendo doesn't have other games close for release that could fill the first half of next year.
Finally, just a side note, some people think there is no time to reveal new hardware before Zelda, but Switch, which was an entirely new concept only had 4 and a half months between the October 20th 2016 reveal video and March 3rd 2017 launch. The Switch presentation was Jan 13th 2017, less than 2 months before the device went on sale. We are 5 and a half months before release of Zelda. There is time to reveal a Switch "2" to launch alongside of it.