I think that betrays a misunderstanding of the planning fallacy. The planning fallacy is the inability of humans to instinctively think and account for risks in such a way as to make accurate schedules for plans. E.g. we seem to assume things will go as planned, we do not stop to think about what could go wrong and when and what responses would be appropriate, we tend to underestimate how much work is required, and overestimate how much we will be able to contribute, etc.

It's not that planning is a fallacy, it's that we have built-in fallacies (biases) related to how we naturally go about planning.