The code base could be much simpler and lighter to maintain if we decided to drop backward compat for Python 2 after the next major release.

It would also reduce the CI maintenance overhead.

I would be really interested hearing from users who really need Python 2 compat for the coming years (that is for future cloudpickle releases).

In particular those users' voices would carry more weight if the said users would be ready to invest some time and efforts in maintaining this project with us.