I can't craft stairs, trapdoors, or bark blocks of any wood variety.
The reciepe itself doesn't seem to exist in 1.20.6 or 1.20.5 for any of these blocks. Whether they are stairs, trapdoors, bark blocks, etc. I'm assuming that there are more blocks I'm not aware of, but my single-player world is still pretty new and I haven't gotten far yet. I can use cheats to summon them in or just go into creative and cheat them in, but I prefer not using cheats, as it ruins the game immersion.
Created Issue:
I can't craft stairs, trapdoors, or bark blocks of any wood variety.
The reciepe itself doesn't seem to exist in 1.20.6 or 1.20.5 for any of these blocks. Whether they are stairs, trapdoors, bark blocks, etc. I'm assuming that there are more blocks I'm not aware of, but my single-player world is still pretty new and I haven't gotten far yet. I can use cheats to summon them in or just go into creative and cheat them in, but I prefer not using cheats, as it ruins the game immersion.

Are you using any data packs? If so, try disabling them with /datapack disable <pack name> and check if that fixes the issue.
Remove these datapacks (Vanilla Tweaks). Use /datapack disable as [Mod] j_p_smith mentioned or just delete them from the datapacks directory in your world save. 1.20.6 introduced breaking changes to datapacks so that old ones are likely to no longer function.