Actually this is not important. Because they need to make a living, and with that they have to make some functonality of ClickHouse propritary.

You can scale the pure open source project really far. And if you need more, you do have money to pay for it.

People need to stop thinking that open source is free leech. Open source is about sharing knowledge and building trust between each other. But we are still living in a business world where we are competing.