The creator made the games a long time ago so it’s no wonder to hear some of them are now professionals in videogames, or still on video, graphic design related courses.
The list is sorted by author name-created with software called Game Maker although this doesn’t apply to all of them. The fan made games (the downloadable and playable type) were submitted to the old Super Mario Portal formerly.
Thus, ensuring their efforts won’t be lost amidst the intraweb abyss. themed games submitted from huge fans of Mario between 20.