We can’t link directly to old postsWhat do you mean? Posts in FR? After a certain time the links no longer point to the correct location, due to archiving?
I was wrong about not being able to link to individual posts (see MaryFromMichigan's post). I've never tried to link to very old threads, but I'd expect the thread and post addresses to stay the same (or if there's a change, to have a simple system of updating the addresses).