The 3.0.0 update was the "Final Major Update" for the official Switch version. It added the feature, which completely changed the game from a "level creator" to a "game creator." This is why mobile users specifically search for this version—they want the most complete toolset available to build their own Mario adventures.
If you still want to search on Google, use these terms at your own risk: Super Mario Maker 2 Mobile 3.0.0 Download - Google
Allows players to create their own "Super Worlds" consisting of up to 40 courses. Searching for an official Super Mario Maker 2 Mobile 3
Searching for an official Super Mario Maker 2 Mobile 3.0.0 download on Google often leads to misleading results, as as released on April 22
released on April 22, 2020. It was the final major content update for the game and introduced significant features, including: World Maker Mode:
Having these features on a mobile device would be a dream come true for level designers. Here is how you can actually access them.