If I remember correctly, this feature was disabled because it contributed to the colony's wealth being very high from the start, and thus to disproportionately strong raids.
If and when it will be reactivated, I can't say at the moment, it's in SirLala's hands.

Oh fair enough, only figured worth mentioning because of the description of them, I end up just dev moding in some timber when I destroy them. I was worried it may have been some weird incompat.