So if there's a channel that has been dormant for over 6 months and the channel owner hasn't been active for over 6 months, how would someone take ownership of that channel....

Asking for a friend

Building /coppanouns
Host of the /mls channel. 
Working on @gmgoodmusic
Lover of Music NFTs and coffee

cc @dwr.eth 

Dan has striped away channels from people under these circumstances for the better of Farcaster.  Hit him up directly, I bet if you have a valid argument/usecase he will give it to someone whos going to actually utilize it.  At least he did with /wow or something that blew up