Installing the game as an NSP means you don't need to carry the cartridge. Given that Sonic Forces is a game designed for quick bursts of play—perfect for commutes—having it installed directly on your SD card makes it an ideal "pickup and play" title.
To ensure you have the "Sonic Forces Switch NSP Update All DLC Full" setup working correctly, check the following on your console: sonic forces switch nsp update all dlc full
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