Using Rust in no way requires the usage of pushover licenses. While it's true that many devs are using pushover licenses, there are plenty of GPL Rust projects. You are just focusing on the sensationalized ones that get mentioned in news cycles.
- AGPL Rust projects on GitHub
- GPL Rust projects on GitHub
- Unfortunately, Codeberg doesn't support filtering by license, but there are Rust projects on Codeberg, some of which will use copyleft licenses here.
- GNOME's GitLab is also rife with GPL-licensed Rust projects.