My question is, is there any plan also to demote those accounts that ranked up years ago who does not earn a single merit even though they are here for a long time?
That would pose a lot of problems. Especially if some of the founding members returned to the forum, and that is something that I hope swe can encourage.
I believe that Theymos is aware of the problem, and he has some changes under consideration. One is a rank above legendary, and that would require earned merits. Another is the removal of merits from deleted posts and sold accounts. That would effectively de-rank a sold account, and could reduce merit abuse.
Another consideration is that some bounty managers are requiring earned merits from applicants to their better programmes.