You can't always control what your neighbor does. If you live in a neighborhood with a Homeowners' Association, you can absolutely control the color of mulch that your neighbor uses in their front lawn by reporting the issue to the HOA. But sometimes a neighbor will do whatever they want, regardless of whether an HOA dictates their actions.
It can be frustrating when a neighbor never mows their lawn while you keep yours clean and pristine. While it doesn't technically harm you in any real way, it can reflect poorly on the neighborhood, dragging down property values and whatnot. And sometimes it is just an eyesore. People don't want to live next door to a house that is never maintained and looks shabby compared to the rest of the neighborhood, which is why homeowners' associations are desirable to some.
Some neighbors, especially those who live in "desirable neighborhoods," want to control everything their neighbor does. The dude in this story is one of those people. He wants his neighbor to move her car at 7:30 AM because he's having construction workers come to work on his house. He didn't tell her in advance, so she could've parked the night before, and he didn't tell her where to park instead. He just told her to figure it out, and she's rightfully annoyed.