I've watched American political conventions before, but the stark differences in diversity were so much more pronounced than any that I've ever seen before.
The republican convention seemed to be entirely populated with wealthy looking old white people and a few suit-wearing young republicans with a very very few lonely token minorities occasionally showing up on the very edges of the crowd, while the democratic convention had absolutely everyone represented from every possible walk of life in America. It was really, really striking and a bit baffling that no-one seemed to even acknowledge it from the stage.
I was always bit doubtful when Americans talk about the radical shift in politics coming with the dying off of the boomer generation, but now I completely believe it. There's no way the republicans can even hope to survive in the next couple decades appealing to such a narrow demographic. At some point soon, they are going to have to change their political rhetoric or die out with their aging demographic, so if you are looking for something hopeful in the future look to that.