Seems like the specs for the 2nd generation Switch are becoming more solid and lining up with rumours going back as far as June 2021.
the Tegra T239 is a modified form of the Tegra T234 Orin. Orin is an automotive-focused chipset so the T239 will add gaming features like RTX (believe it or not) and DLSS.
The ballpark estimates put the raw compute around 2.5 TFLOPS, which is faster than PS4 and the Steam Deck. Since Steam Deck can run desktop PC games like Spiderman comfortably, it's promising for the Switch 2. Plus, seeing that it has native DLSS support integrated, it puts 4k upscaling on the table.
I expect they'll stick with a 720p screen; in fact they may not even upgrade from the current exceptional OLED panel.