Personal opinion here...
There’s a role for both. I believe that understanding a concept deepens the learning and retention of knowledge, but memorising facts or principles is also important especially when some things are just the way they are, and there’s no straight answer to a “why” question about that fact. When memorised points (eg. The multiplication table) are repeated often enough, the knowledge can also be retained through the years.
Different people do learn differently, so it’s good to have a variety of learning modes and techniques, especially for children in schools. Creative thinking and critical thinking are also important skills to pick up, even to question why the answer given by the teacher is right, or coming up with other ways of deriving an answer.