How to understand what sets us apart from competitors?
Start working near your main competitor or on their platform. Open your shop door to door, start selling on eBay or Amazon. We should still be able to sell and to see our competitive advantage and its best seen in a head-on fight.
Analyze what our customers stopped doing after they started using our product. What they stopped doing is our competitor. Our competitive advantage is the reason they stopped doing it. Sometimes neither competitor nor our competitive advantage is obvious.