Witness decentralization is in process and there was just lately news that new witness candidates will be announced soon.
https://twitter.com/ObyteOrg/status/1095977601271820288Witnesses are behind TOR so they are not vulnerable to DDoS, but you don't know that because you just like to FUD without actually learning how things work. Apparently, you don't even understand the difference between the hub and witnesses.
The witnesses are not anonymous, they are tangible by name and thus also their technique.