I basically got the same impression from a phone call I just had with someone from Cox. He asked what equipment I'm using (HDHomerun Prime with Plex for live and DVR). Then he asked if they were DRM compatible which suggests to me that DRM wasn't a mistake and isn't going to be removed.
I wasn't sure of the answer to that at the time but after looking it up I have discovered that the HDHomerun Prime tuner is compatible with DRM using their native apps for live viewing (and I confirmed that I can watch all the channels live that I could before with their app) but DRM is not supported with the Plex Media Server live or DVR. Interestingly the HDHomerun DVR is not DRM compatible either.
Without being able to use the Plex DVR, the CableCards and thus Cox are of no use to me any longer. Guess I'm cutting the cord.