I was thinking of using it with Duckdb as well but seems it would be of limited benefit. Parquet objects are in MBs, so they would be streamed directly from S3. With raw parquet objects, it might help with S3 listing if you have a lot of them (shave off a couple of seconds from the query). If you are already on Ducklake, Duckdb will use that for getting the list of relevant objects anyway.

Maybe the OP is thinking of reading/writing to DuckDB native format files. Those require filesystem semantics for writing. Unfortunately, even NFS or SMB are not sufficiently FS-like for DuckDB.

Parquet is static append only, so DuckDB has no problems with those living on S3.