On the left is The Legend of Zelda: Link’s Awakening DX for Gameboy/Gameboy Color. On the right is The Legend of Zelda: Breath of the Wild for Nintendo Switch.
Link’s Awakening weighs in around 1MB(!) and Breath of the Wild weighs in at roughly 13GB(!).
It’s amazing how technology has advanced in the almost 20 years since both games were released from each other, resulting in smaller cartridges being able to hold much, much more data.
I don’t have my original Legend of Zelda cartridge to compare, but at least the Gameboy cartridge helps bring some insight for this comparison.