Thumper doesn't have what I look for in a rhythm game.
First of all, it's not a music game. The sound design is great, but the rhythms you follow aren't really music - just simon says that happens to align to a beat grid, but doesn't really do much of what makes music fun to listen to.
The way it works is that the sounds of objects appearing is a few beats ahead of when you interact with them, so you can't even hear the rhythms being played too clearly because they start overlapping with much louder sound effects related to your actions. So yeah, audio is not musical, it's just gameplay feedback.
Thumper is also a troubled rhythm game. As with any title in the genre that decides to play sounds when the player acts, it can't adjust for audio and input latency, meaning your brain will always have to fight between the urge to press a button on beat and the urge to press it so that the sound effect ends up playing on beat.
I very much hate how little the game cares about making the sounds of the rhythms you're meant to follow clearly audible. There's a lot trial, error, and memorisation that could've been replaced with a much more fun and tense mental challenge of actually getting the chance to hear what you need to do and figure it out on the fly. As it is, rhythms past a few notes just disappear behind the sound effects that don't actually give you much useful information.
All that being said, the game's presentation, gameplay feedback and the actual manual challenge are pretty great, so if you click with it, you'll enjoy it a lot.