[amlozano]

You aren't the only one that has noticed:

https://0ver.org/

More seriously though, for these projects, the first version is version zero. If they make no major backward incompatible changes, why would they ever release a version 1?

[rokob]

Because version 1 is the first version with any actual guarantees: https://semver.org/spec/v2.0.0.html#spec-item-4