I think it's not a simplistic comment at all and you are missing the devastating impact that lack of funds has had on schools.
The lack of funding has been going on for 13 years and there has been a drip-drip effect of teachers leaving, TAs being made redundant, subject offers that might be more appropriate for less able students being withdrawn, pastoral support being limited, SEN needs not being met.
Then we had the pandemic. That has hypercharged all these issues. Mental health issues in children have gone through the roof and CAMHS which is the agency which should be supporting children with this has collapsed. SEN needs have also shot up without any increase in support (more likely decrease) to meet them.
Post-covid it was recommended that the govt invested £15 billion in a package of recovery for children. They said no. And here we are, dealing with the fallout.
It has been reasonably well publicised that there is an attendance crisis in schools. Part of this is mental health related, part increase in sickness absence related, part is poverty related, among other issues.
What isn't as well publicised is that there is also an internal truancy crisis. Kids who are attending school but not attending lessons. These kids may well end up in the toilets where teachers can't get to them.
Only half the required number of secondary teachers were trained last year, only half the required number are being trained this year The situation in schools where they are being held up by a very few experienced staff, some inexperienced staff and a whole bunch of supply teachers (who may or may not even be teachers), with kids who are increasingly disaffected, unsupported and impacted by a variety of societal issues is a recipe for disaster.
People understand that there's a crisis in the NHS when you phone for an ambulance and one doesn't arrive. They understand that you can't expect a police officer to investigate a crime. We're now in the situation where you can't expect a convicted rapist to be sent to prison because there's no room.
Why anyone would expect schools to be able to function normally is beyond me.