I did this exact thing this year. I moved about >5 TB of event and log data into Clickhouse. I went from having to increase Postgres storage capacity every few months ($$$) to never thinking about it. Migrating to Clickhouse took me from constant timeouts on analytics queries to all queries returning in well under 100ms, and automated data retention using TTLs going from nightly pruning jobs that failed constantly (Postgres hates DELETEs on large tables) to again, never thinking about it. Because of this, I was able to increase retention per-account from a mere 30 days like I had -- just to keep performance and storage costs under control -- to much, much longer. Huge fan.