And yes you also see residential buildings on main roads. The reason this is a residential and not main road is due to its size and position away from through-traffic. It’s a road where you have a quick look and then just cross, main roads are of the “eh I can look but I probably need to get to a crossing to get across” territory.
And no there’s no speed bumps why would there if the road is narrow enough and people naturally drive slow enough, there’s no through traffic, the residents don’t race on it, etc.