IMO a better question that should be debated is if merit is an appropriate indicator for someone to be able to have influence on the trust system
Probably not. But merit is a good method to keep account farmers out of DT-voting, and I think that's why theymos uses it.
Using merit will prevent a farmer from voting many times with alt accounts, but only to the extent he does not receive merit. If a farmer receives merit, they can effectively distribute that same number of merit to their alts in a circle (they may distribute less in order to avoid suspicion), and would potentially have an outsized influence on on is on DT.
Theymos has said he will blacklist anyone who is using alts to get into DT1
I have also argued in the past that I believe merit tends to be given to posts the person awarding the merit agrees with, which I predict will result in a cycle of those in power having more power, and any transgressions by those in power being overlooked.
Ultimately it comes down to:
if it is appropriate for many people who do not trade (participate in the marketplace) to have an influence on the trust system