Now the problem arises from the interchange with exchanges. Since you got an existing asset, and are seizing existing funds of people, that would mean that exchanges accepting this code are also accepting the removal of funds of people outside of the scope of the actual protocol. None of the people whose funds were seized got their funds in an illegitimate way (through hacking or similar, like in the case of Ethereum). Thus, that is actually quite complicated.
In the case of Hive, a new asset was created and people got this NEW asset based on a set of rules. That is fine since no ones existing assets got altered in any way.
In terms of security, I hope you are doing your math right, the vast majority of the votes on the witnesses on the steem chain comes from steemit inc. While only 20-30% of the votes on the hive chain come from freedom + blocktrades. The problem arises if one single legal entity is able to vote in/out all consensus participants. (That's why Tron was assessed a security in a recent lawsuit).