For many years, local maps were my day-to-day work.

Regulations dictated that north should be at the page top, but exceptions were made so that the relevant land mass would efficiently fit on standard paper sizes. For example, you could fit a lot more detail onto a printed map of Japan with the paper as Portrait, rather than Landscape. So the practical aspects of the printed paper age have long been a side factor in map orientation.

And there was no doubt that the exceptions, where maps had north other-than-up, proved mentally more difficult for everybody to deal with. People not used to working with maps would struggle because it didn't align with other maps, and people used to working with maps would struggle because our minds were locked into the convention that came from 95% working with north-up maps!