I wonder if they have considered moving back to ClickHouse. ClickHouse Iceberg support has improved a lot over the past few months. You can easily run stateless ClickHouse on top of Iceberg. This solves the tenancy issue, and it can easily handle petabytes scale [1].
[1] https://clickhouse.com/blog/jump-trading-uses-clickhouse-wit...
But why even bother with ClickHouse? What's wrong with Trino?
Author here. We didn't leave Clickhouse. It still drives most of what Posthog offers. I missed that bit of context in my post I admit. Instead we are looking into a new stack we can give customers so they can run their warehousing workloads on it instead of the centralized CH.
Stateless CH on Iceberg sounds interesting, we looked into it but Delta/Iceberg had other downsides for us.