Struggle is very good for learning, I remember as a child enjoying very difficult interfaces because I was proud of being able to navigate the software when I finally get there, becoming very efficient with it, and I learned way more about the domain. (I'm thinking for example Cubase, reason, Photoshop at the time, most linux softwares, vim,...)

While easy to use softwares are more 'enjoyable' and the dopamine reward is high for small actions, it also prevent to develop some ability and resilience in navigating harder things. When the software complexity increases, users get annoyed and don't use it correctly because they were never exposed to much complexity before. (thinking about medical softwares that require many many actions to encode a patient, finance softwares, etc..)

Now, not all softwares are made to improve one efficiency. In your case, the app allows a children to express its creativity in other ways, which is very valuable also. So I think it is good that the interface and the interaction are easy, the focus should be on the creativity and not on the manipulation.