Whether he is replaced or not doesn't really matter. There's no definite number of merit sources to do the job. Theymos can decide to use lesser or higher number of merit sources. The emphasis is on how much merits is in circulation and not who are those circulating them.
It does matter, for what purpose the inactive merit source be still in the list if they cannot do the job, nothing. There are a lot of merit sources application that deserves in the list. I don't know what reason theymos is holding on that inactive sources but it doesn't make any sense if they are inactive on such very long time.