These studios have profit margins in the multi-millions, they could afford a symbolic $100k donation. Instead they choose to push their developers through another crunch cycle.

They typically pay a lot more than $100k for Unreal and the likes or employees working on their in house engines.

Oh and these studios often lose money instead of having profit margins in the multi-million, see Ubisoft.

But ConcernedApe uses Monogame for Stardew Valley, the studios don't use Monogame. Why would they donate?