It is the most stable, feature-complete version of the game. No further content updates came after this, making it the ultimate "complete" state.
The update 3.0.2 for Super Mario Maker 2 demonstrates Nintendo's commitment to supporting and improving their games. By releasing regular updates, Nintendo ensures that their games remain enjoyable and engaging for players, even after their initial release. SUPER MARIO MAKER 2 -NSP--Update 3.0.2-.rar
Once you have the game running on version 3.0.2, you unlock the full Super Mario Maker 2 experience: It is the most stable, feature-complete version of the game
Be aware that using NSP files often requires a modified (homebrew) Nintendo Switch console and may carry a risk of being banned from online services. Refer to the Nintendo Switch Support page for official update methods. It is the most stable