SQL Server stored procedures don’t provide a separate tier of T-SQL functionality. Anything they do to the data can generally be expressed and executed as a T-SQL batch. If you think you need stored procedures to avoid network roundtrips in the middle of your transaction logic, you’d be wrong.

Stored procedures are essentially a crude, database-bound API layer. For serious application development, a proper service layer provides stronger contracts, authentication, testing, versioning, observability and source control in a sane general-purpose language, ideally the same one you’re already manipulating the data with elsewhere.