A product can feel simple to use only after someone has done the work to handle complexity behind the scenes.
A simple interface is not proof that the underlying problem was simple. The product may need to manage edge cases, make sensible decisions, and present only the information a person needs at that moment. Making those choices well takes design and engineering effort.
There is a difference between removing options from a screen and making a complicated task feel easy. The first can be cosmetic. The second requires understanding the whole process, including the parts that fail or confuse people. When a product feels straightforward, a lot of careful work may be hiding in that experience.