They are not. Dried chopped onion (or onion flakes) is the lowest on the scale of dried onions when it comes to intense flavor. Next, is minced onion followed by onion powder. Because onion powder has the most flavor, you'll always want to use less if you're substituting it for either dried minced or chopped onion. Onion flakes come in bigger pieces than minced onion, so you can always crush the onion flakes to match the size of minced onion and use it as a 1:1 substitute.