In contrast with these limited platforms:

SNES Doom - 128KB RAM, I think a 2MByte ROM, CPU is 65816 at 3Mhz + SuperFX RISC CPU at 21Mhz, which also had its own 64KB of RAM.

PSX Doom - 2MB RAM + 1KB fast scratchpad, able to load from a standard 650MB CD, CPU is a MIPS R3051 at 33Mhz + the PSX accelerated graphics, not used except to draw strips

So doing this in a device that has not too much more RAM than the SNES and also has to livestream the VGA signal Atari 2600 style is exceedingly impressive. It's a dual CPU unit but basically having to spend a core manually bit banging the VGA signal like that is what fascinated me the most.