I wonder what the sentiment would be if the situation was reversed. Here we have a developer effectively looking to pay below market rates for artists, and then unsurprisingly not finding many good artists willing to do that long term. Not a judgment on my part, just saying that he's looking to keep the art budget to an absolute minimum. Instead if it was an artist defending his choice to make relatively simple games…
I'm one of the players that's on the margin between his graphically "good" games, e.g. the Avernum remakes, which use a vaguely consistent colour palette and are comfortable to play, and his graphically awful games, e.g. the first Geneforge, which has an eye-stabbingly bright green border around the game area that's brighter and higher contrast than the actual content, making playing the game fatiguing and uncomfortable.
Jeff's games don't need 3D art or a big budget or even a totally consistent style, they just need a tiny amount of good UX taste and a few hours of photoshop to mess with HSV. Thankfully, the more recent titles do have better UX.