kaikun97 wrote:Even with double screens the processing power needed for the DS should still be lower. It only has a 60-ishMHz cpu compared to the 333mhz the psp has.
DS and PSP emulation are really hard to compare. PPSSPP uses a lot of HLE, which it can do because the PSP's OS/SDK software is installed on the PSP itself and therefore you only have to reliably emulate one set of it. The second processor (media engine) generally wouldn't have to be emulated at all, as opposed to DS where ARM7 is emulated (it only runs Nintendo approved software but the libraries included are game-specific)
This also means that for the most part there isn't much in the way of low level peripheral accesses made by the game code. This is in stark contrast to DS games that have a ton of this and it turns into a lot of overhead. PPSSPP uses hardware acceleration for emulating the GPU (with many options to try to tweak how it works), something that's more straightforward to do with decent performance because there's no concern about having to combine it with the output of separate 2D engines.
Besides all that, few PSP games actually run at 333MHz, 222MHz is more typical.
kaikun97 wrote:Also if I rightly recall, Drastic DS is partially a hypervisor on ARM devices because of the similarities of the DS's ARM9 and modern ARMv7 and v8 CPUs on phones or am I wrong?

There's nothing resembling a hypervisor/virtualization in DraStic. That's a common mistaken assumption people have it. It uses a traditional recompiler.