Comment by pseudohadamard

That's not just the BBC, it's any broadcaster, because it costs nonzero dollars, time, and effort to move something online that they have no idea whether anyone cares about. Our national TV archives are like that as well, tons of stuff in vaults but if you want to see it you need to contact them and ask for it. I did that for some zany 80s comedy that they had listed but wasn't online, a few weeks later it was online, they just needed an indication that there was some interest in it.