For 27 years I worked with telegrams -- the predecessor of email. Virtually anything was advised that way and sometimes, in a period when phones were scarce, it was the only way. But it was brutal.
Anything that is going to cause emotional upset should be done face to face whenever possible.
The worst case I ever heard of was a woman I worked with. Her fiance had gone to London to work. She was to join him there after six months and that's where they would be married. When she arrived in London she found that he was engaged to somebody else and he didn't have the decency to tell her before she travelled half way around the world.
She was a lovely woman, AE: gentle, thoughtful, friendly, happy. Well, happy until that happened. We worked together for a few years after that and although she seemed to get back to normal there wasn't as much laughter in her eyes. And who could wonder about that?
Anything personal that can cause distress, should be delivered in a face to face discussion. The only thing I can think of that might be given a free pass is a birth announcement to anyone who is not an immediate family member or very close family friend.
Love it. Then there was the story of the Parisienne who was raped by a German soldier. As he buttoned up he said, "In nine months you will have a fine little boy. You may call him Hans." She looked up from the ground where she still lay and said, "And in a few days you're going to break out in a rash. You can call it German measles if you like but that isn't going to help."
Benedict Arnold 