I’ve got skin in this game and this is probably outing, but…
as i understand it, school streets is not designed to block residents’ traffic to houses within the closure zone, but it would stop residents passing through. So for a couple of times a day it might be less convenient for some residents, but would also make the through roads quieter
As others have said, the primary aim is to improve safety at the school gates - this has been a huge problem at out school, and some parents just do not care as long as their little darling is safe (I have actually had someone argue with me that their parking on the zigzags is for the safety of their children).
Active travel is a secondary aim of these schemes and in my mind they are more suited to urban areas. Our school catchment is <1 mile in diameter, our school walk is 15 mins max (child’s pace), and so many families drive (only to drive straight home again). I do have sympathy for people going on to work, and do drive when that is the case for me, but I park a little further over as it helps with step count and means I don’t get stuck in congestion. Many non-work related activities are non- time sensitive and so the 10 minute walk home (sans kids) is no issue.
There are huge benefits to active travel to school for children and communities (well-being wise but also emissions), this is something we should really embrace. I’m really going to miss the school run when my kids leave primary.