At TransferWise we recently migrated to TimescaleDB for all our FX rates data.

So, there's two use cases for us:

1. We use it to ingest tick-by-tick FX rates

2. We use it to query historical rates e.g. whenever a users opens our homepage we query it directly from TimescaleDB

We've battled tested it pretty hard now & haven't run into any scaling issues - been very much plug & play.