Just passing someones else thanks to Epic as UE4 baking is really good to performance but preserves so much quality on lighting side.
This demo for example ran so well on old AMD pc setup that is almost 9 years old(rx 270 in only new). Half-Life 2 - Apartments (Unreal Engine 4) - YouTube
My notes to Epic would be please optimize as much possible Editor side of baking functionality.
If someone has even older pc then please let know how well this HL2 testscene runs on your pc.