From my experience after a couple days of scavenging, it seems that the former residents of Tahoe have changed from a bunch of jocks that liked to swing weighted bats and toss their old bones out, to a bunch of intellectuals who collected leather bound books and had lots of clothes.
I have found one bone crafting recipe, so they are rare but there.
I haven't scavenged any weapons parts, feathers, decorations, etc. I think that non-rare item tables are messed up. The cloth, leather, screws/nails/rivets/bolts, spikes/small sheets/rods and cash/buttons/beer tabs are showing up too frequently and preventing feathers, weapons parts, bones, and buckles/decorations/rubber scrap from appearing.
The new rare items that I have found or heard of fall under metal/plastic boards/sheets/pipes/poles. People wanted distributed rare items to encourage trade, but there are two big problems with this:
1. These items are too heavy to trade. One or two of these items will put you over your max encumbrance.
2. There are no known recipes that use these items.