Motherduck is hosting duckdb in cloud. DuckLake is a much more open system.

Ducklake you can build petabyte scale warehouse with multiple readers and writer instances, all transactional on your s3, on your ec2 instances.

Motherduck has limitations like only one writer instance. Read replicas can be 1m behind (not transactional).

Having different instances concurrently writing to different tables is not possible.

Ducklake gives proper separation of compute and storage with a transactional metadata layer.