The song that plays while editing an underground level in the Super Mario Bros. theme contains a looping piano segment extremely similar to one used in Dave Brubeck's 1956 song "Take Five". It also contains drum sections in the rhythm of the same song, though played at a faster tempo.

Part of the newly implemented Athletic Theme that plays during sky levels in the Super Mario Bros. style plays a portion of the results theme from the arcade game VS. Super Mario Bros..

Originally the development team consider using Bowser's car from Super Mario 3D World for Mario to drive around in the Super Mario 3D World style, but they instead decided to go with the Koopa Troopa car because of how difficult it would've been to replicate Bowser's car in Super Mario Maker 2.

Super Mario Maker 2 is the first Mario game to be released during the Reiwa era – the reign of Naruhito as Emperor of Japan – following the abdication of Akihito on April 30, 2019. To commemorate this, Nintendo of Japan's Instagram account posted a video concurrently with Naruhito's ascension on May 1 where Mario travels through each of Japan's imperial eras since the franchise's inception, with each one being represented by a different style in Super Mario Maker 2. The Super Mario Bros. style represents the Shōwa era (Hirohito's reign from 1926 to 1989), the Super Mario World style represents the Heisei era (Akihito's reign from 1989 to 2019), and the Super Mario 3D World style represents the Reiwa era. Coincidentally, although Super Mario 3D World was released during the Heisei era, it would later be ported to the Nintendo Switch in 2021, two years after the Reiwa era's onset.

Many international Mario fans were confused by the design of the Angry Sun in the New Super Mario Bros. U style of Super Mario Maker 2, noticing how it appeared more stern than angry. This is due to the fact that "angry" is not part of the enemy's name in Japan, just being called "sun", meaning that anger is not an inherent part of the character and giving it a different expression would make more sense without knowledge of its localized name.

The new design of the "Angry" Sun seems to be based on pre-colonial mythology based on the sun, most particularly the Inca sun god Inti, a design inspiration that seems to exist in anthropomoprhic suns from multiple other Nintendo games such as The Legend of Zelda: Ocarina of Time, Mole Mania, and Kid Icarus: Of Myths and Monsters

The Training Course from "The Super Mario Bros. Movie" was recreated in a promotional video posted by Nintendo. It recreates several scenes of Mario failing to complete the course from the movie.