The article is more or less completely accurate.
There's one very specific and narrow exception, which (AFAIK) doesn't actually cover any consoles in that listing. If there are any consoles that are purely NMOS (2600? VIC-20? C64?), then (and only then) would ignoring voltage translation be ok. (
last time I said this)
Code:
.................
5V : ..............
| : :
| nmos : :
| +-+ : : 3.3V
---| | : : |
| +-+ : : _
| : : ^
| : : |
+-----------------------+--...
| : : |
| +-+ : : |
---| | : : |
| +-+ : : _
| : : ^
| : : |
gnd : : gnd
console : : rom/fpga
................. ..............
nMOS pullups aren't very good at finishing things: they can't drive the output all the way up to the voltage supply. The MOSFET ceases to conduct once the difference between the voltage on its input ("gate") and output ("drain") is less than the "threshold voltage". So
when the 2A03 is driving a pin, it will pull up strongly to about 4V and then stop. 4V is only 0.7V above the 3.3V supply, or roughly the expected forward voltage of the overvoltage protection diode. So,
in this case, it'll conduct only a small amount of current without even needing a current limiter. It'd still be better (if supported by the 3V devices) to run them at 3.6V.
Note that the NES's RAMs are still CMOS, and the caveats in that article still apply to them.