Talk more about the product you built (What worked, what customers said, how was it improved overtime, what did you learn from customers using the product and talking to them), rather than going in detail about the technical requirements of the product (Used technology, improved loading time by n%, rewrote using a different framework).
And the reason why it's important is because startups fail because of bad value propositions, not lack of technical expertise.
As someone who describes themselves as such and has had good success - demonstrate that you care more deeply about the success of the product than "technology" itself. Code is a tool to solve those problems - focus on what has worked and not worked in coding, rather than what is cool and exciting. Its more of a mindset thing than anything - spend enough time actually being interested in business problems rather than CS problems.
If you want a product focused career path, start getting "product" in your job titles. Every employer knows I'm a product engineer because "Product Engineer" is on my resume.
Like others have said, the rest is mostly about the way you talk about what drives you. Solving hard problems is nice, but demonstrating that you can think well about building something people want is what you should aim for.
Is it the particular things they have worked on at other jobs, i.e. their experience, or is it the way they talk about what they want to build?
I'd be really interested to hear how I can make myself sound like more of a product programmer.