Yes, atm it relies on Tinybird. But the level of trust you need for that is different. And the data in Tinybird is encrypted so even if you don't trust them to run a Clickhouse database, if you set an encryption key they won't be able to do much with your data.
We are planning to support a version that doesn't rely on Tinybird at all but stores all data in your browser using indexeddb.