They are just very bland and a little musically incoherent. They pass the basic sniff test of, "this sounds like music" but the more you listen the more they fall apart. It's a good muzak generator, but that's about it.
Remember all the people who said, in January and February of 2020, this "novel coronavirus" is not a big deal? Because it affected only a tiny amount of people? Because "much more people die from the flu"? The fallacy is that they ignored the speed at which it progressed.
It seems like it's trained on entire soundwaves. I'm curious if you'd get a better result by training it on transcribed MIDI and then taking the output MIDI and plugging it into VST's.
Seems like you would still get that "central brain" compositional approach without the garbled sound quality and unidentifiable instrument noises.
From a music producer standpoint if that's the quality for classical music, could definitely create some samples.
It has multiple structural layers of a sort, which is progress over a few years ago. But they're still a long way short of the huge but intricate structures in real classical music.