> you can design a unique identifier system that does not allow tracking
You can (sortof), but we run against that trust issue again. If I'm giving a unique identifier to someone, I have no way of knowing if their assertions about its use are accurate. Even if they are, there's no guarantee that won't change in the future.
> If all you want to do is get a good estimate of how many users use what types of configurations of your software (major and minor version)
You're talking about the perspective of the publisher. I'm talking about my perspective as a user. A company's "need" to collect metrics is their problem, not mine. If their solution results in more information disclosure than I'm comfortable with (and a unique identifier absolutely is), then I will avoid their software or block communications to their home base.