I know Anthropic models have a lot of insane, paranoid filters, but I don't remember them blocking cryptography work last I checked (some 3 months ago now).
3 months ago is like years ago in the current AI landscape
The cyber filter blocks really basic stuff all the time. People who are pro that bs should be forced to only eat with a spoon for the rest of their life.
I routinely get rejected on elliptic curve related requests; often I can talk Claude back into some work on it. But it is surprisingly sensitive to talking about research cryptography in my experience. I’m not in their cyber program.