Is there a way, another fora than arbcom, where the
community can discuss
this issue - decide how we'll use the word "founder" and settle it for
good?
Yes, RFC, but you say you've already tried that. RFC's don't really
work unless the people involved are willing to listen to the comments,
and it sounds like some aren't.
I don't really see how there can be any reasonable arguments for any
position other than simply describing it as disputed. Wikipedia does
not exist to settle disputes, we don't decide who is right in an
argument, we just report on the argument.