@Wman1996 It's up to CESA at this point to update Mario Maker 2 numbers, and apparently there is a delay with the latest report, so we might not know end of 2023 and later numbers for a while, if at all.
Mario Maker 2 has definitely underperformed because I would've expected it to be long past 10m by end of 2022 anyways. I agree that people would much rather play official levels than make their own. Doesn't help that it launched just 6 months after NSMBU DX, and the final update was less than a year after launch.
I feel like for the Switch 2, they should release a new 2D Mario around 2027 and then make Mario Maker 3 essentially a paid DLC add on for that game a couple of years later.