Solved without context so here I am trying to explain the what and the why:

• there is only one config per runtime on the main thread but py-game is not py and it's an exception to this rule because each game might have different dependencies and whatnot
• because of previous point, you can have multiple py-game scripts with different configs on the page but you cannot ever have multiple py scripts with multiple configs: first come first serve
• this difference is because py and py-game share basically nothing ... you can think about py-game as mpy, it's literally something completely different from regular py but it's also experimental to see how or if that helps instead of causing confusion

To me, having two completely different script types help explaining why one can be multiple times on the same page and the other doesn't, but it's true that so far py-game didn't bring in enough goodness to justify its presence and various developers have been confused about its capabilities and, most importantly, differences in regard to regular py script ... I hope at least it's clear why a config for py is ignored in py-game unless it's explicitly used/pointed at via a config attribute.