Theory: Within the Super MakerMatic

Abstract
Mario Paint, Mario Artist, Super Mario Maker, and Super Mario Maker 2 take place within the Super MakerMatic.

Arguments

 * Argument 1: The Super MakerMatic 21 is a device that was built by Dr. Crygor in WarioWare: D.I.Y.. It can be used to make Microgames, Graphics, Comics and Records in WarioWare D.I.Y., which is very similar to the creation options in Mario Paint (Art Creator, Graphic Creator, Music Creator and Animation Creator) and the creation options in Super Mario Maker (Course Maker and technically a form of Music Creator).


 * Argument 2: If the Super MakerMatic in WarioWare D.I.Y. is number 21, it stands to reason that there would be Super MakerMatics 1-20. Mario Paint being a previous version could potentially explain this.


 * Argument 3: Gnat Attack from Mario Paint reappears WarioWare D.I.Y. (As the Microgame “Fly Swatter”) & Super Mario Maker.


 * Argument 4: If you name your project in WarioWare D.I.Y. “Mariopaint” the music will change to match that of the music from the original Mario Paint. Multiple characters from the Mario Paint editor as well as the Mario Paint UI are reused in WarioWare D.I.Y., Super Mario Maker & Super Mario Maker 2.


 * Argument 5: The Coursebot from Super Mario Maker and Super Mario Maker 2 is clearly based on the unnamed robot that saves paintings in Mario Paint. They even both share a theme tune.


 * Argument 6: Super Mario Maker 2’s Story Mode doesn’t make a lot of sense and both contradict other games in the series and itself. It is implied through Mario’s job descriptions that many of the levels he’s playing through were constructed by other people attempting to make platformer levels. It doesn’t make a lot of sense for seemingly random people to have the ability to completely terraform the landscapes of Mario’s Planet just for fun.


 * Argument 7: Peach’s Castle is destroyed in the intro, yet it appears in the background of Grassland-themed New Super Mario Bros. U styled levels in the Story Mode. This doesn’t make sense, but it could be explained by Super Mario Maker 2 being a game in-universe.


 * Argument 8: After Toadette is saved from Bowser, she states it’s the first time that she’s seen Bowser up close. This makes no sense. Even if we were to ignore all of the spinoffs where Toadette and Bowser can be/are close to one-another, she still would’ve faced him during the events of New Super Mario Bros. U Deluxe, and New Super Mario Bros. U cannot take place after Super Mario Maker 2 as it features as a style in Super Mario Maker & Super Mario Maker 2. If this Toadette was merely an in-game character, this wouldn’t be an error.


 * Argument 9: Mario having different abilities in different game styles also doesn’t make sense in-universe. In-universe, they shouldn’t be actual different games that have different aesthetics and mechanics. For example, Mario shouldn’t just turn into a Super Mario World Sprite and lose the ability to Wall Jump and Ground Pound but turn into a 3D model and regain those abilities in the next level. However, if it was an in-universe game with those mechanics purposely implemented into the in-game Mario it would make a lot more sense.