Don't know if it was a typo, but 50Hz and 60Hz not
Mhz.
No NTSC 64 does rgb as standard. The early NTSC ones and one French PAL one can be easily modded for rgb. Apart from those machines, the rest all need heavy modification to get rgb from them (building a replacement dac).
64 is not the last console to demonstrate problems, how I wish it was

.
A huge number of ps1 games are shocking conversions.
Sega tried to bring sanity back to the world with most Dreamcast games supporting 60Hz.
Sony dragged us back to the dark ages with shocking conversions again and no 60Hz on most games until late in the consoles life and even then, only certain devs.
Xbox & Gamecube are a mixed bag, but doesn't really matter as most games have a 60Hz option.
Now Nintendo tries to drag us back to the dark ages with 50Hz VC games and even worse people are buying them
60Hz is always preferable, even what are considered good PAL conversions have issues. PAL Ikaruga drops animation frames so that it runs the same speed as the NTSC 60Hz version.
Soon as the consoles switched from hardware selection, over to the software selecting frequency (N64 onwards with exception of the Saturn), there was just no excuse to not have a 60Hz option.