As I said, the amount of Shader Cores are 6x. And T239 will (probably) clock higher than Tegra X1 and won't be as bandwidth constrained as TX1 was. While, of course, there are others structures that might not scale as much, a 6x performance jump should be very straightforward to achieve.
If we look at the BoTW 4K60 Gamescom demo, for example. It's taking a 900p30 game and upping it to 1080p60* (A nearly ~2x jump in pixels pushed per frame) and then upsampling it to 4K thanks to DLSS. That's a small jump, but it showcases how much more powerful the hardware is to push a Switch game to 4K60 with no sweat.
* I assume it's taking the OG BoTW Resolution/FPS targets of 900p30 and rendering at 1080p60. It could be that the demo is rendering at 1440p60 or another value and then upsampling to 4K60. If it's rendering at 1440p60, it would be a a ~5x jump in pixel per frame compared to OG Switch.