If he writes like that no wonder he got no responses. Instead of writing like ChatGPT or one of those spammers who spam spam spam’s my LinkedIn everyday he made the effort to understand people and write a personal note himself he’d have gotten a much better response rate.

Your market research has probably provided you with a good sense of your potential customers. Reach out to them explaining how you're satisfying a problem they have for less than they've been spending taking care of it themselves. It also helps to show up at industry events. People are far more responsive when they can see and talk to you in person. It's been a minute since I've worked at a startup and getting a business off the ground but that was the gist of it.