If the Nintendo 64 was entirely passively cooled, surely the Pi can be? Mind Nintendo/SGI had much more surface area to work with so this is probably an unfair comparison.
According to random unsourced claims I just found on an internet forum, which I've decided to trust:
NES: 9 watts
Super NES: 10 watts
Nintendo 64: 19 watts
GameCube: 39 watts
Wii: 45 watts
PlayStation: 17 watts
Game Boy: 0.7 watts
Game Boy Advance SP: 1.6 watts
The rasppi 4 is supposedly 4 watts when idle, and under 8 watts when loaded.
(So there is really no question that a machine like this can run with passive cooling, but obviously it's going to be a function of case size and design, as well as heatsink size and design.)
The Nintendo 64 has a U shaped piece of aluminum spanning the width of the console that screws through the RF shielding and into heatspreaders on the RDRAM, CPU, and RCP. It's about 2 RasPi's long by itself :P