Mother noodlé had the same experience doing teaching assisting. I know this verges on Gammon talking points (and Mother noodlé is a little Facebook-boomer-brained) but there is a problem with a lot of parents who’ve abdicated responsibility for their children to state institutions. How much is down to poverty and general lack of community support, and how much is down to some people just being shit parents is moot when it comes to what is best for those children and their prospects of not carrying the same issues to the next generations
Primary school libraries won’t fix that, obviously, but they are at least something that can be done.. and aren’t going to do harm. It’s a choice to use resources that way, of course, and the trade-offs matter.. but it’s no use saying stuff like ‘why do this when there is food poverty’ because a) food poverty can, and should, be dealt with in addition to literally every other thing that government can do or does do and b) nobody is actually making a choice between libraries and food.
For the record, I actually don’t know where this library idea is coming from. I can easily imagine that any of the UK parties would come up with it. I would want anyone implementing it to be clear on whether the money to pay for it is explicitly coming out of other services (noting that money is fake and it does come under the realm of something that could be done with zero impact on other areas of government spending.