If you'd like to elide the extension, not rename and are creating the pex via

./pants binary

then I don't think it'd be unreasonable to add an option to the

PythonBinaryCreate

task (https://github.com/pantsbuild/pants/blob/a70377c842a6b037635d3fc86b42bdd12a2112b8/src/python/pants/backend/python/tasks/python_binary_create.py#L140) so that the extension default could be switched globally in the repo with a pants.ini setting. I think it would also be reasonable to add a parameter to the

python_binary

target to allow said-same at higher precedence (https://github.com/pantsbuild/pants/blob/8efe62815b07953931c315bd8b4cc8ae08e24e14/src/python/pants/backend/python/targets/python_binary.py#L37). This is sufficiently narrow that it might be a perfect avenue to test ease or not of contributing pants fixes, which is likely part of life as a pants user.