We talk about sharding vs. chunking in the blog post and I would put CitusDB in the former category. More specifically, TimescaleDB is focusing on time-series workloads. To handle time-series workloads, CitusDB suggests combining their extension with a third-party extension (pg_partman) (see their docs).

I have no experience with this combination myself, so don't want to speculate about performance, etc., but when reading the docs it really seems like an afterthought.