Yes, it's great. Part of the issue is that PostgreSQL isn't great at parallelism yet so optimizing the storage greatly reduces compute time to begin with.

Unfortunately that extension has a bunch of limitations and issues that keep it from being production-ready. PostgreSQL could really use a proper columnstore table implementation, and there's a pluggable storage API on the roadmap but it hasn't gotten much traction yet (and is focused on an in-memory engine first).