They don't optimize for it and I suppose the data distribution is primarily aimed at parallel OLTP rather than OLAP. Just wanted to mention that design-wise it is similar but that's indeed not all there is to it. I'd be hesitant to store large volumes of data on a single PG instance; don't see how a single-writer, filesystem-based database is suitable at all for data that is large enough to warrant columnar storage

so, what would be your db choice for OLAP?

You can also go HTAP with TiDB which has TiKV for OLTP and TiFlash (Raft-based columnar replicas) for OLAP.

I am more interested in actual OLAP than HTAP, and don't see strong OSS OLAP offering on the market right now, my rants in previous discussion: https://news.ycombinator.com/item?id=36992039

But I should look at TiDB, they looks like interesting and relatively mature project.

https://www.starrocks.io/ is on my shortlist for OLAP

its also on my list, but it looks like not easy to try, setup procedure is complicated.

No expert but I'd say you'd rather be looking at bigquery, Redshift, Clickhouse, Snowflake, etc.