I'll edit the original question. This would be in regards to any wear and tear on the transmission. My cousin had brought it up when he was riding with me and I would put it in neutral and coast the rest of the way.
But he works on semi's, so he was saying that's what he was told about them.
Having a license to drive pretty much anything on wheels, I can tell you the reasons he saying that are:
A: Semi's travel a lot more miles and haul a lot more weight.
B: By putting a semi in neutral and coasting to the stoplight, you're using a lot more air using solely the brakes to stop. The brake systems are air brakes, the lower the air pressure, the less your brakes work. And even running, it can take a bit for the pressures to come back up. That's why they run jake brakes and use the trans/engine to help brake, especially in town.
Your car will be fine either way.
