The irony is that what “Hamilton” represents now is exactly what opera used to be: a thrilling, contemporary, immersive stage presentation that’s a union of story, text, music, image and movement, and that gets under the skin and into the blood of a wide audience that feels it speaks profoundly to them. There’s something addictive about “Hamilton,” and that’s partly a result of spending three hours fully concentrated on sound and spectacle, straining to get every word, alongside hundreds of other people doing exactly the same thing. You don’t get that from a recording. Nor, often, do you get it in an opera house