It's a bit of a tricky comparison because snowflake, and a lot of other tools that get referred to as "modern data stack" are very vendor based. If you're using snowflake, you're probaby using it on snowflake provided architecture with a whole load of proprietary stuff. You can't "swap in" snowflake on the same hardware like you can with spark, daft, duckdb, polars etc.
That said, iirc benchmarks normally place it very similar to spark. It's distributed, so I'd be very surprised if it wasn't in the spark/daft ballpark rather than polars/duckdb.
The delta format is Databricks lakehouse file format, snowflake uses iceberg I believe.
Both Snowflake and Databricks also provide a ton of other features like ML, Orchestration and governance. Motherduck would be the direct competitor here.
Saying that there are now extensions to query snowflake or databricks data from duckdb for simple ad hoc querying.
Duckdb is fantastic and has saved me so many times strongly recommended.
it has had a combined SQL and dataframe engine since March 2015...
How we work with data is simple, if SQL+dashboard solves the problem then we do it in Snowflake, if we need something more advanced, then code + bunch of SQL.
Pretty sure ML engineers work in different ways, but I don't know that side well