"Show, don't tell" is not an absolute dogma. As with anything else, it depends on the needs of the particular story.
Agreed. It's definitely contextual. It's often necessary in terms of world building in order to set the scene for what's to come, and when done well, it can really add to the story.
However, I hate it when it's simply a wall of text. The recent terrible World Without End miniseries did this, being the first thing you see, and it took away from what they could have shown and felt incredibly cheap. In a way, it did set the tone because the rest of the miniseries was incredibly bad.