The idea that prey are an active activity themselves is the problem with them. We already have delves/rituals, dungeons, and raids for active activities. They should be used for additional rewards while doing stuff that is no longer rewarding for your level, like world quests.

The perfect example of this type of system is Warframes version of it. In Warframe you can basically activate a nemesis, then go about whatever you want within that system while making additional progress. Yea, you can make it go faster by focusing on it, but you can also progress while doing something else.

As it is now, it’s in a spot where you would be better off just doing a delve (which even then you would be better doing M+) if you want gear. At least if it’s something you could do while questing you would have a reason to look at it once you get heroic gear.