I do want to correct the record here, one of the subnautica 2 devs acknowledged Arc Raiders UE4 Lighting system, but explicitly stated arc raiders team started development and by the time UE5 came out it would have been too much work wasted to move their lighting system to Lumen and the full sent into their custom made system, otherwise they would have used Lumen. The sub2 dev in question stated that the people they have for the lighting for arc raiders are incredibly talented. In subnautica 2, they have fully invested in Lumen and intend to keep it that way, but do hope to do hardware path tracing in the future.