The GIL does not prevent race conditions in your Python code. It only prevents race conditions in internal data structures inside the interpreter and in atomic operations, i.e., operations that take a single Python bytecode. But many things that appear atomic in Python code take more than one Python bytecode. The GIL gives you no protection if you do such operations in multiple threads on the same object.

Are you writing an extension or Python code?

If you are writing Python code, the GIL can already be dropped at pretty much any point and there isn't much way of controlling when. Iirc, this includes in the middle of things like +=. There are some operations that Python defines as atomic, but, as I recall, there aren't all that many.

In what way is the GIL preventing races for your use case?

Looks like according to the PEP it may eventually be default in 4-6 releases down the road: https://peps.python.org/pep-0703/#python-build-modes