There are interesting bug that can explain "nobody is there": link on main /kc/ page to IRC is wrong (at least for me):

https://qchat.rizon.net/?channels=%endchan

It opens web UI with #%endchan channel as default, so, if user doesn't know about all these channels, he'll get into empty channel.

It is pretty strange, because link on thread page (i.e. /kc/res/...) is ok: https://qchat.rizon.net/?channels=endchan

Link on main page is also ok, although it has different case: https://qchat.rizon.net/?channels=Endchan
IRC channels are case-sensitive by RFC, but looks like rizon or web ui ignore it (don't know who doing it though, looks like UI).

I don't understand why there are different links - do this site really has different top headers, at least in board/channel interface? They look same, so why different templates?

But whatever, here is the possible problem.