I think a fair amount of unpleasantness in recent years has come from this disconnect: some people think that by publishing on crates.io you're making some promises (that they might not assume simply for, say, having a repository on github).
To me, using an extremely generic name like 'base64' does suggest that you're in the second camp, and so that you might expect to have a conversation that feels more like "we're equals building this project together" than "I'm the maintainer and my judgement is all that matters".
I feel like most of these issues stem from the very young age of Rust (2015 -> v1.0). Give it a few years and these problems will stabilize as the long term crates will survive and the short term will grow stale.
I see the arguments against organization/namespacing in Rust (ala Maven or NPM) and I kinda shake my head. The reality is, crates.io is a crazy bazaar, people end up taking crate names and then abandoning their projects, leaving that name forever unusable.
e.g. at work we have an internal crate named "event" (on our internal repository) that conflicts with an abandoned public crate of the same name that hasn't had commits in 8 years. This leads to confusion if you get your cargo config wrong. But it's also kinda frustrating that this very generic name is ... lost to time now.
https://internals.rust-lang.org/t/blog-post-no-namespaces-in...