I spent 8 years developing all the art for my own game platform and another 4 years on the next... so
..
"also, it would take an absurd amount of time" ? Yeah? Well while you search for shortcuts or hope for a free ride, you're not making the art you need or want. What constitutes an "absurd" amount of time is pretty relative. If you hope to make a sizeable amount off your game, maybe it will take what seems right now to be an absurd amount of effort. It only seems absurd because you haven't connected with the reality of spending your time 24/7 making things. i.e. putting out the effort to earn the acclaim you hope for.
Slightly a side story, so no one complains: In 1994 when I was 14, "Heart of China" came out and VideoSpigot came out and all I wanted for Xmas was a video camera and an interface to record short QuickTime movies in locations around my house, so I could string them together into a dark futuristic CD-ROM game. (in SuperCard, if you're wondering). That would have solved all my problems creating art!
It wouldn't have. Make your game as a sketch with whatever sketching tools you have...but don't expect technology to rescue you from needing other humans to make it good. AND DON'T UNDER-RATE OR UNDERPAY THOSE PEOPLE.
Because trust me, if you're disappointed that AI isn't giving you good enough art, you're no visionary. You haven't even tried people.