And yet you yourself have posted on the last pages of BOTH ...doing your own bit to keep them from dying a death.
And...
Both are authored by Frogboy so it's a brave lad who'd be willing to cull them....
You CAN be your own worst enemy....
One of them is a sticky and the other is the top result for a search on 'multiplayer' so even if nobody replies to them for months they're still more likely to be replied to than a fresher, more recent discussion on multiplayer. It doesn't matter that I've replied to them, I would still be on the last page for months at the current random posting rate.
Also, the 'hot topic' icon appears besides topics that have been dormant for ages, so you can't rely on that as a reliable indicator of whether the topic is really hot or not, all it says is there are lots of replies.
Basically your forums favour old topics that go on for years, even if forum users might be better served by a new topic which highlights the important and relevant points from the older topics and moves on from there. I'm not saying that anyone will actually do that, but it would be pointless for them to do so when the old topics still attract the occasional post because they scream to the top of the search. Catch-22.