Your instructions (rules) about comments may be conflicting with system prompt (instructions from Cursor).
From mostly toying with LLMs on Perplexity, there are many ways how to strengthen your instructions. From a simple assertive language You must not use comments., to “screaming” You MUST NOT use comments!, formatted instructions <code_style>concise without any comments</code_style>. Especially if your instructions are longer, you may want to repeat or reiterate those which seem to be not adhered to or are important to you, eg You are an expert programmer who writes code without comments. ... OMIT ALL COMMENTS., or ... Remember the code rules: no comments (... denotes other parts of a prompt).
Though a bit of a warning - if they indeed conflict and Cursor uses code comments to, for example to state file names, it may worsen your experience. (I don’t know what system/pre-prompt they are using.)