At this point in time and even more by the time the Switch' successor comes, it will be smarter to bet on a chip and display that are capable of VRR (Variable Refresh Rate) like the XBsX and PS5. No more 30, 60 or 120fps, just constant smooth gameplay.
Nvidia is still interested on mobile GPUs, and this article from last week proves it: https://wccftech.com/nvidia-geforce-mx-400-turing-notebook-gpus-tackle-intel-xe-dg1-and-amd-vega-igpus/
That's a laptop GPU, not mobile. It even says that it competes with Intel and AMD. Tegra was Nvidia's failed attempt to take on Apple and Samsung phones. It was a great chip, though...