Nintendo Switch

The old cartridges held the data uncompressed. In read only memory that slotted directly into the system bus. There was no loading the game after pushing the cartridge in.

Modern systems have data with multiple compression formats. Held in hierarchical file systems accessed through separate devices on the system bus. That don't have the speed or latency of system memory. And even compressed modern games still take up to 3 million times more space than old cartridge games.