Hi, I can see two planters on imagery. Which would block car access but allow cycle access, and possibly motorcycle access. I've made changes in following changeset
https://www.openstreetmap.org/changeset/134139668

I've added barrier=planter, and motor_vehicle=no; foot=yes; and bicycle=yes.

Can you confirm this was there recently?
Do you know if Motorcycles can get through the barrier.

The road is still privately owned by the developers, and has not been taken over the council. When the council adopt the road I assume the council would make it official with a traffic order.