PlaybackLoudness can be used to detect spikes in the summed amplitude of the sound, but it seemed a bit delayed last time I used it. I think Rhythm Track plays the audio ahead of time and uses PlaybackLoudness to position premade or formulaic patterns across the a, s, k, l, and spacebar keys.
Unfortunately there’s no way to read amplitude at specific frequencies on the spectrum so you can’t parse out sub tones to easily distinguish the song’s beats.
If you know the songs BPM ahead of time you can generate points based on that timing.