The most profitable opportunities online right now aren't in saturated markets, they're in the gaps between saturated markets where two audiences overlap but nobody's serving the intersection (so how do you find these gaps before they close?)
Most people look at a crowded market and think "too late, I can't compete" so they either give up or try to out-execute everyone else with better content or lower prices but saturation in two markets actually creates opportunity because the overlap between them is almost always underserved or completely ignored.
Think about it like this: there are a million people teaching Instagram growth and a million people teaching email marketing, but almost nobody teaching Instagram-to-email specifically for coaches who sell high ticket offers. That intersection is a market of maybe 50,000 people who need both skills applied in a specific way, and right now maybe three people are serving it well.
E-commerce is saturated, SEO is saturated, but "SEO for DTC brands selling supplements on Shopify" might have two real experts serving it. Everyone else is either too broad or coming from only one side of the equation.
What makes intersections profitable is that you're solving a compound problem, someone in the gap doesn't just need skill A or skill B, they need both applied together in a way that accounts for the unique constraints of their situation. That's harder to deliver so fewer people do it, which means less competition and higher prices.
The formula for finding these gaps is simpler than you think: pick a saturated market you understand, then ask what adjacent skill or market that audience also needs but isn't getting served well. The key is adjacent, not random, it has to be something they naturally encounter as they try to solve their main problem.
Example: if you teach people how to grow on Twitter, the adjacent need might be "what do I do with followers once I have them" which leads you to monetization, or offer creation, or audience conversion. Now you're not competing with growth people or monetization people, you're serving the specific intersection of "Twitter creators ready to monetize but don't know how."