No, the artwork of a single artist was not the main inspiration for the game. This artstyle has existed for decades. Starting from Designer Republic/Wipeout which was the first big example:
Additionally, there is artwork from the Art Director depicting the style of robots used in Marathon dating back 11 years on his public posts. This is before the artist Antireal existed.
Here is a breakdown of this artstyle’s history:
https://xcancel.com/poellll/status/1923675496740458567#m







