As @skyschermer says, someone else’s policies do not dictate what is enforced against you. Imgur also does not intentionally host executable code. Imgur also requires an email address when you sign up.
DMCA is likely a primary, though probably not the only regulation to be concerned about here. I’m not qualified to do a proper legal analysis of crates.io’s position, but I can only imagine (and gladly accept in good faith) that the crates team has had such an analysis done, and has concluded this policy is the best one to accomplish whatever goals need accomplishing.
It occurs to me that copyright and patent concerns aren’t the only ones crates.io deals with day-to-day, and that perhaps other concerns are driving the decision that this is the best (though perhaps not only) way to comply with DMCA requirements.
Validated emails are a norm on the internet, and it is extraordinarily easy to create one to use specifically for any service you don’t wish to be personally identified on, while also relieving that service of the burden of possibly having to maintain other contact information.
I think my point, wholesale, is that if you don’t like the policy because you have some concern with US government actors, that regardless of your feelings, we can’t offer you much relief.
I understand that crates policy changes tend to ruffle feathers because we all rely on it so much, but they’re not any less subject to the laws of the nation they operate in than anyone else, and they have to make the decisions that best allow them to keep operating as they do now, while being protected from legal claims.
