You are correct that his teacher previously worked with middle and high school students. However, he also teaches several other 5th graders from other schools who aren't that much older so he has some basis of comparision as well.
Aside from the neatness and spacing, he also has trouble writing small enough to fit into boxes, which become more and more of an issue in the older grades. It isn't normal around here. Most other children in his classes do not exhibit that kind of difficulty at all. Same thing with left and right by this age. It's that obvious so DS noticed. It may be that DS will be making the tiny hand movement (picking up a pencil?) to remind himself. If it is fast enough, then it won't matter so much.
