IMPOSSIBLE OR NOT: Does Intuitive, No-Research SEO Exist?

Here's the deal. I'll create useful, super high-quality, well-written content while keeping the user needs and intent in mind at all times. I'll write in a way that contains relevant keywords (according to my intuition) in titles, body, metas, and alts. And that's it. Wouldn't that rank as well?

I see so many people in the affiliate site business focusing on SEO, keywords, etc first. And then they create content. But I know my niche for over 15 years. I know what people want. I live my niche. What do I miss out on if I just write excellent content and spread it on social media?