I am careful about coins whee previous coins can be exchanged for new coins. Many times the hodlers of the previous coin have no liquidity and when changed to the new coin they dump as soon as it is listed. How will you guard against this when handing out the 50% pre-mine to previous holders?
Well, let me start with the fact that it is not yet a fact that all 50 million will be distributed, so far the swap is very weak. So I do not think that everything will be distributed, even if they included another coin in the composition of my project, there will still be no full distribution.
A lot Of Koson coins were lost with FCB exchange, a lot were just lost and deleted by users as unnecessary to them, a lot of old BlackRose were also just lost. So don't worry too much about it. About protection from such a. Coin is such a thing that is simply impossible to protect from such possible actions, so here I would not be able to do anything, and would not want to, I believe that the market should be free and everyone has the right to decide what to do with coins.
I don't know what happened at FCB exchange, but what if its owners decide to swap coins that were held on it?