Air carrier Captain reported receiving ACARS message of a schedule change for the first officer flying. Captain reports this as a repetitive disruptive safety hazard since pilot loses concentration affecting sterile cockpit and CRM.

Narrative

45 min prior to our expected touchdown in DFW; an ACARS message was received that advised my FO of a change to his schedule. This continues to happen routinely now and I believe it is a safety of flight issue. As soon as that message is read by the affected pilot; they are in the yellow and distracted. As we should be briefing the arrival and expected approach; now the crew is distracted on something entirely avoidable. How no one from the company or FAA is concerned about this; is beyond me. The affected pilot is now off in another mindset; and this leads to missed radio calls; missed call outs; and just overall distractions that we are trained to avoid. Yet these messages keep being sent by scheduling at busy times in the cockpit. I tried to keep the distractions to a minimum; and going sterile cockpit early to try and get back in the green. These messages effectively remove one if not both pilots from the normal routine and in the loop; and every time this happens; I know it's going to make the arrival to landing phase of the flight a challenge. This is a safety of flight issue.I suggest this type of distraction be immediately ceased. I don't know how the FAA can be OK with this type of distraction just prior to an arrival into a busy airport. I'd love for an FAA observer to watch this exact scenario unfold in real time; and tell me the crew is not distracted. I'm sure if you could see this I happen in real time; you'd know exactly what I'm talking about because the errors that need to be trapped go up are easily recognized. Distracting ACARS message sent just prior to arrival. I tried to implement sterile cockpit early to try to put distraction at a minimum. This distraction should cease immediately. Causes many avoidable errors. This effectively removes a pilot from the loop; for a time; as he/she has to weigh the aftershocks of what a scheduler is trying to do to their life. If you've never seen the effect of this in flight; then you won't understand what I'm writing about. No more distracting ACARS messages during flight. During flight; that stuff has no bearing on the safety of the flight; and should not be sent because it only serves as a distraction. One day this type of distraction will cause a big enough issue that you can't avoid it. I hope this ASAP is taken seriously.