“Apps like Signal have essentially no control over what content Recall is able to capture, and implementing “DRM” that works for you (not against you) is the best choice that we had.”
Signal had to turn on a DRM flag to stop Windows from screenshotting private chats. Microsoft shipped Recall without granular settings that would let an app protect itself. The protection also stops at your own machine. If the person you are messaging runs Recall, your words land in their searchable database anyway.