Why it's important to write for just "One Customer" per product page/landing page.

If there's an AI tool that writes code and also writes copy. That's two target customers in programmers and marketers that the product serves. Ideally, you should create two different pages on your website for their different use cases. If you merge the two use cases into a single page and both target customers are going through that page, a marketer will switch off and say this product is not for me when he sees things like coding and a programmer will also switch off when he sees things like copy when going through that page. This hurts your conversion. That's why you should rather create two different pages for these two target customers and send traffic to the relevant page. Also, potential customers will feel that the product was made for them specifically, hence increasing your chances of converting them.