+1 we ended up adding something to our CLAUDE.md specifically to counter it. Something along the lines of "comments should be treated the same as production code, they shouldn't leak the content of conversations and stand the test of time". It doesn't always work, as other people say claude stops following these the more its context window gets filled, but now it's mostly a matter of telling it in a new session to review the changes against the guidance on comments and clean them up.