Fundamentally Wagner's Dream is about Jonathan Harvey, not Wagner, whose presence exists to set off Harvey's music. A poem is not a legally binding document. Art by its very nature is a creative response to stimuli. Uncreative people often don't understand.
For example, there was (anecdotally) a college professor whose genius lay in attracting funding. He built a machine that could be programmed to write music. Each bar took endless calculation and misery. Along came Luciano Berio, who, with a chuckle, played with the program and came up with wildly spirited inventions. The professor couldn't understand what Berio was doing and raged in resentment. But Berio was an artist not a data processor. But there'll always be more professors than Berios. One mark of troll is that they're jealous of those who do what they can't.
Harvey is a composer I just don't get but that's me, not necessarily him. I just couldn't get my head around Wagner's Dream. Here's a piece in Opera Today by Colin Clarke, who appreciates Harvey better than most.