I disagree with that ruling, and I have some serious problems with sanctions against entire countries/regions, but it definitely makes sense that LE would interpret it as being impacted by OFAC.
Now, does this serve a policy purpose? Perhaps not--US computers trust plenty of non-US CAs that could continue to serve these customers. But that's not how comprehensive sanctions are set up, they are effectively a complete embargo.
A better question is whether telecom carveouts (general licenses) in the sanctions may allow this. That is a country by country question as each one is worded differently.
And here: https://github.blog/news-insights/policy-news-and-insights/a...
In an alternate universe, Let’s Encrypt has a chat with someone and then states, publicly, like a speech, that they think that person owns a domain.
In our universe, Let’s Encrypt lets a client open an “account”, enters into a contract with the client (the contract is the topic of this entire post), and gives the client an API by which the client requests a certificate. Then Let’s Encrypt grants the certificate. Maybe the certificate is somehow speech. The rest sure doesn’t sound like speech to me.