Novice Network needs to be opt-in only in light of the recent population surge.
By that, I mean mentors should be required to manually join it whenever they log in or get removed due to inactivity.
The reason is that a lot of people get their mentor certification almost strictly so they can have the crown icon by their name and/or gain access to mentor roulette, not because they're actually interested in...y'know, mentoringand offering advice to new players.
The game, however, shoves all new mentors into there automatically and also initially flags them to auto-join Novice Network whenever they log in or switch zones. This leads to the limited 100 mentor slots being occupied predominantly by people who have no actual interest in helping, meaning at prime time the people who are helpful frequently end up being locked out for several minutes if not hours at a time.
The mentor system as a whole could use an overhaul, but I feel like this is the bare minimum they could do for the time being to help ensure Novice Network is fulfilling its intended purpose; particularly with the bloated numbers of new players around.