My understanding on the whole issue was that it came back to how the charter was written. ABC was sued on the basis of not allowing women when the membership requirements contained no language upon which women could be excluded. Conversely, WIBC had a set of rules that specifically limited membership to women.
Tying in with 'bones other thread on city championships, there should not have been a problem with conducting an ABC Men's city championship if they were willing to write their rules with the necessary language.
The language has everything to do with it at all levels...the PBA used to specify male as a membership requirement just as the PWBA specified female. The PBA has since modified its language to incorporate all bowlers that meet the membership requirements.
Just as a league can require that all bowlers belong to the same organization (ie. work group or other similar group) by writing the rules to create a closed league, there should be no problem in creating a male-only league. The question potentially becomes whether the league has anyone with brains enough to properly draft the rules...and perhaps more importantly, to represent the league in the event the matter gets brought before the local association.