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).
Well yes, like I said it's not really a true columnstore. It's a basic storage extension that writes table data as ORC files for good compression and in the best-case scenario can managed to filter out segments. It's missing all the fancy processing features that real columnar warehouses use so it'll never be as fast.
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).