If Luck be a Landlord generated the same gross revenue on the Epic Games Store, TrampolineTales would keep approximately $2,755,976 - that's $659,177 more than on Steam.
At this revenue level, Epic's concrete platform fee would be $239,451. 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 $2,096,799.
Note: This is a hypothetical comparison. Actual sales volumes differ significantly between platforms, and Steam's larger user base typically drives substantially higher sales.