The Pages Lane entrance from Maldon Road is wide enough for a van, let alone a car. Following that end of Pages Lane to where the pathway starts, Pages Lane does not get any narrower.
There is then not really any differrence in wideness during the footpath section leading up to The Sea Wall.
What does change on Google Maps is the terrain. The terrain of Pages Lane would be suitable for cars. The terrain of the pathway would be suitable to walk and cycle. It is no longer a road, but a pathway to The Sea Wall.
Bamber would have no trouble cycling a flat pathway as wide as a van on footpath quality terrain for 0.4 miles. A few hundred yards from where he used to live & now worked.