I believe this makes the cure much worse than the original illness. I often prototype and throw a lot of crates in Cargo.toml from memory, even with versions. While I see name squatting potentially annoying, I've not hit an actual problem there and even if I did, it would be not often. Having to look up or memorise the suffixes would be constant papercut every time a new project is being created. This would be annoying on daily basis, for all rust users, not just crate authors who can't publish a crate with the name they've chosen.
Besides, as a crate author, I'd try to avoid the name collision despite the suffix, to make sure people don't mistake my crate with some other. But someone could create a „colliding“ crate later on.