We understand that the road is closed, that's pretty obvious from the massive steel barrier shielding the huge orange digger. But still the red and white sign is a necessary notification.
It's helpful to know which way to travel as we can no longer continue straight on. The yellow sign that says 'Diverted traffic' and points to the right does that job perfectly well.
The contractor has the right to advertise his firm.
The other four signs (six if you count the cones) are unnecessary, ugly, make the street considerably more unpleasant and are insulting to my intelligence.