Switching away from Python would not fix this. EVE Online runs its world without instancing or shards, meaning you cannot scale out the simulation when a single zone is overcrowded. Pretty much every other online game avoids this problem by making it impossible to have thousands of players in the same area because networking every players' actions to thousands of players is always problematic
But one of EVE’s biggest selling points is specifically the 1000s of players in one area.