Here is an interesting tidbit: the Japanese version of the SNES was called Super Famicom. There was a physical notch that prevented Japanese cartridges from being used in the North American SNES. But for people who knew, it was actually possible to just cut off the notch in the North American SNES, and then you could use Japanese cartridges. My cousin gave me a Japanese Star Fox cartridge back in the days and I could…
As far as the SNES is concerned, PAL consoles simply letterbox the video and run the game 16.6% slower. Occasionally the game speed is modified to account for the decreased framerate. Super Metroid's engine was sped up so that gameplay was faster frame-by-frame and approximately as fast in wall clock time, but this introduced a number of bugs.
It wasn't until framebuffer based consoles like the Playstation where using the extra lines of PAL signal became common. Game speed was still a common issue until the Dreamcast and PS2 where game speed ceased to be an issue and optional 60Hz support was also common.