Why is every crate pre-1.0?

It seems like the semantic version of most crates in the eco system are pre a "1.0" major version. Any thoughts on why this is? Isn't this a problem in the Javascript ecosystem with Node in that packages can introduce breaking changes at any time?

Some examples:

1. chrono = 0.4.23
2. log = 0.4.17
3. pyo3 = 0.18.1
4. rand = 0.8.5
5. nalgebra = 0.32.1
6. pretty_env_logger = 0.4
7. winit = 0.27
8. image = 0.24.5
9. json = 0.12.4

Are some examples from crates I use often.