For current members, your initial merit score is equal to the minimum required for your rank. Of that, a certain amount (less than the usual half) is spendable. The spendable amount was calculated based on your current rank and the number of activity points you earned in the last year. A Legendary member who hasn't posted in the last year would still be Legendary, but would not have any spendable merit.
I don't agree with this, this is just like giving the "old members" (including me) a head start. I'm not saying that earning merits is a race but giving us a head start also means giving us a free reputation out of nothing. That does not necessarily mean we need to rebuild our reputation from zero, I mean there are so many members that have earned a good reputation on this forum.
So I think the merit points for old members have to be given based on their reputation now and without affecting the rank.
I assume you mean trust when you say reputation.
Trust is trade reputation, merit is post reputation,
they don't have to be directly connected (eg I
wouldn't trade with QS, but they can write pretty damn good texts).
As merit is a direct requirement for getting ranks, they only way to do this switch is the way it was done right now.
They can't "not give the merit" but let you keep the rank.
Either you gain the merit and keep the rank, or nobody has merit and we all are newbies again.
Then you'll have a problem on how to distribute your initial sMerit to kickstart people gaining merit and rebuilding their previous ranks.
But this is not just about reputation as in the market, it's also about reputation as a "good poster".