is this highway definitely closed? and if so, is access physically blocked?

740 Designs
139 Balcatta Rd Balcatta WA 6021 Australia
(08) 9240 6273

INFO@740DESIGNS.COM.AU

https://www.740designs.com.au/
Whether you're moving in to a new home or investing in a property, you will need to refine its interior design to be sure it is a luxurious and welcoming area to stay. However, many of us can hardly fit a five-minute rest into our busy timetables, which makes going from store to store looking for stylish and high-quality home furnishings almost difficult. 740 Designs is here to bring your home the makeover that you are worthy of, beautifying the place for your possible buyers.

The speed limit for High Road is 70km/hr from Leach Highway to Nicholson Read, with a possible 40km/hr zone during school arrival & departure (between Meadowbrook Drive & Belvedaire Way)
School zone
40 kph on school days
7:30–9am and 2:30–4pm (or as per signage)
https://www.police.wa.gov.au/Traffic/Road-safety/Road-Safety-Information

This area should be a small park with a footpath through the middle

wikidata suggests, that there is Arthur River here. Maybe the Blackwood River is badly named. Please check.

this is a private driveway by the looks of it

The place has gone or never existed. This is an auto-generated note from MAPS.ME application: a user reports a POI that is visible on a map (which can be outdated), but cannot be found on the ground. User comments: "mislabeled; the correctly labelled building is across the street " (OSM data version: 2016-12-14T16:41:03Z) #mapsme

This area is Sid Eaton Reserve

"closed down"
The place has gone or never existed. This is an auto-generated note from MAPS.ME application: a user reports a POI that is visible on a map (which can be outdated), but cannot be found on the ground.
POI name: eleven squares
POI types: amenity-cafe
OSM data version: 2017-10-20T12:20:02Z
#mapsme