If Tom Clancy’s The Division generated the same gross revenue on the Epic Games Store, Massive Entertainment would keep approximately $63,477,641 - that's $8,879,786 more than on Steam.
At this revenue level, Epic's concrete platform fee would be $8,519,678. Epic charges 0% on the first $1 million in annual per-app revenue and then 12% on the remaining amount. On GOG (30% cut), the developer would earn approximately $50,398,123.
Note: This is a hypothetical comparison. Actual sales volumes differ significantly between platforms, and Steam's larger user base typically drives substantially higher sales.