you can check for yourself:

https://learn.microsoft.com/en-us/azure/databricks/ingestion/auto-loader/

"Auto Loader can ingest JSON, CSV, PARQUET, AVRO, ORC, TEXT, and BINARYFILE file formats"

And it makes sense. Autoloader is a tool to identify what you have already processed.

Delta lake is more than just some files, it has a transaction log.