I think it's fair to call out a dark pattern for account deletion (which, for better or worse, is common practice) - but the data training and data retention thing can both be disabled...I was much more surprised that they DIDN'T train on data as long as they did, when every other LLM provider was sucking in as much data as they could (OpenAI, Google, Meta, and xAI - although Meta gets a pass for providing the open-weight models in my head).

Anthropic has made AI safety a central pillar of their ethos and have shared a lot of information about what they're doing to responsibly train models...personally I found a lot of corporate-speak on this topic from OpenAI, but very little information.