Tho very rare, why would you use a database that is at risk to be erased completely, and with a limited set of queries as the main DB? Honest question.
My concern was the performance of Postgres when it's receiving thousands of writes per second. I assumed that such a task would be more suited for Redis, then the data could be filtered and sent to Postgres for longer storage (or some storage solution such as S3).
I think bigger issues would be time related queries when dataset gets bigger as opposed to write speeds.
I think a time series database is best suited for this kind of project (timescale build on top of postgres, influxdb, ...)