An OLTP solution fixes a lot of the headaches about the traditional extract-load-transform steps.
Mostly a lot of OLAP starts when the data loads in Kafka logs or a disk of some sort.
Then you schedule a task or keep a task polling this constantly, which is always prone to small failures & delays or big failures when schema changes up.
The "data pipeline" team exists because the data doesn't move by itself from where it is first stored to where it is ready for deep analysis.
If you can directly push 1-row updates transactionally to a system and feed off the backend to write a more OLAP friendly structure, then you can hookup things like a car rental service's operational logs into a system which can compute more complex things like forecasting of availability or apply discounts to give a customer an upgrade for cheap.
Neon looks a lot better than YugaByte in tech (which also talks postgres protocols) and a lot nicer in protocol compatibility than something like FoundationDB.
Alloy from Google feels somewhat similar, Spanner has a postgres interface too.
The postgres API is a great abstraction common point, even if the actual details of the implementations vary a lot.