I'm not sure which framerates were used on SMS games, but I remember a bunch of Dreamcast games (that I used to play on an old CRT from the early 90s) had you c

I'm not sure which framerates were used on SMS games, but I remember a bunch of Dreamcast games (that I used to play on an old CRT from the early 90s) had you choose between 50Hz and 60Hz when starting, so clearly CRT TVs were capable of using signals higher than 29.97Hz.