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Let's Encrypt bans certificate usage by residents of US-sanctioned countries [pdf]
(letsencrypt.org)
For true stories that are so ridiculous, that you could have sworn it was an !theonion worthy story.
Yes. It would be by global consensus rather than at the whim of an individual.
Here's the latest list I could find, and they're clearly not the same.
https://www.sanctionscanner.com/blog/list-of-sanctioned-countries-by-ofac-un-and-eu-2025-1103