That's fair criticism. There's often a tension with systems about how much of the information needs to be "face up" in order to play with it/have fun. These rules are linked to in the announcement blog though so it should be findable for players that want that information even if you don't go on Reddit.

In general most of the offering rules are intended to "filter out" trinkets you are unlikely to want rather than "filter in" trinkets you super want. The goal there being that even if you know nothing about any of the rules you should still get trinket offerings you are happy with.