I think the merit system seems fair! Although I'm not sure about the reasoning behind the decision initially,
but basically higher rank = people can earn more from bounties, which seem to be the primary reason for many people to use the site.
Merit system = reward quality content = fill the site with quality content which might attract new users?
The system is not a perfect fairly system, but it is fair enough for the forum users.
In addition, it is a really fair system for all newcomers after the launch of merit system in January of 2018. All newcomers since that point have the same starting point, have the same odds to earn merits; and only really deserved users can rank up due to merit system effects.