>>33283866They say that because they think the performance issues of the 3DS games are due to GameFreak themselves rather than system limitations. 3DS hardware is better than the Nintendo DS and GBA before it but it's still more than a stones throw away from Wii and Wii U in terms of graphical capability, especially since the PICA is from the early 2000s and was clocked to make battery life last.
Switch is a modded Tegra X1, but it's far more modern ARM tech by comparison so the worst I expect is Battle Revolution visuals in HD.