The core problem is that for someone knowledgeable in the field, everything becomes straightforward, but the further away you are from the field, the more novel it becomes -- this is true across the board. Even the great accomplishments where people win Nobel prizes, often it can be argued that it was going to happen anyhow because it was the next step in scientific progress given the context.

Thus defining "non-obviousness" is super hard to do -- because it is all context dependent and humans are like a million monkeys inventing everything that can possibly be invented in aggregate.