In order to do this, they need their own token
I completely disagree and also find it worrisome that you seem to assume this to be taken for granted or obvious.
It is only true if you assume that proof of brain is going to be used in a community, or that it is a good idea to begin with (fewer and fewer seem to accept this notion). Communities only need to be able to determine their own distribution rules. This does not require a new token, and imo it would benefit everyone more if it instead used STEEM.