Answered via Discord by @klye:

Softfork 0.22.2 is a fork that has been approved by 18/20 witnesses, making it the current approved version of the steem blockchain software. This fork was community contributed and removes the ability for Steemit, Inc. owned accounts to vote for witnesses, proxy votes and transfer steem from their accounts. It is a softfork because it can be reverted in the event that we wish to undo it. This was done in the https://github.com/SteemDevs/steem/tree/0.22.2 repository.