Unbalanced pool of interested candidates is a factor, that's true, but the lack of interest is again a "boys club" syndrome from as early as school. And it's not like this "boys club" only happens at school stage and goes away at the workplace stage.

There are some physical jobs that have some gender bias due to their physicality. Software development is not one of them. This is like debating e.g. covid deniers or whatever nutjobs you will, not worth my time but not evidence fearing.