> The subject matter may as well be discrimination as no valid legal reason was given for action taken against a group of people otherwise.

All decisions are discrimination, and discrimination in general is fine. There are narrow, specific kinds of discrimination that are suspect and need additional justification. OTOH, a perfectly valid reason was offered: legal advice based on international sanctions imposed on Russian entities in response to Russia’s war of aggression in Ukraine. Now, certainly, there was not public information sufficient to assess the correctness of that decision, and I would not prejudge any claim from any party adversely impacted that chose to challenge it.

But I’d also note that where there is not a contractual relationship or some other binding commitment to way against the potential consequences of sanctions violations, legal advice will likely be “better safe than sorry” in that it is better to cut off relations where there is no commitment more broadly than sanctions might require rather than to err on the other side, too. Acting in such advice mag still be a reasonable and prudent decision.