Before 1.20.2 (Pre-1), if custom/modded server sent Stonecutter recipe, that contained custom nbt in the output item, Vanilla client would display it without issues. Since this pre-release (or likely earlier snapshot), it is no longer the case.

After checking the serialization code with Fabric, it looks like recipe constructed from packet doesn't copy nbt into new/recipe-bound ItemStack, while still writing it to the packet. While it doesn't affect vanilla servers, it still breaks functionality from previous versions. See attached images for comparition between 1.20.2 and 1.20.1.