I'm wary of trusting anything in that article, as mentioned above it is only-one sided. It is not easy to PEX a child...
One of the main problems is that the Academy may get a lot of support for the exclusions from parents of children without disabilities or behavioural issues.
'I'd be glad to see the back of him' was the feeling among several parents at my son's primary school.
I have no doubt other parents want to support the exclusion of disruptive children, but this is not only in academies, and is very unlikely to influence the school's decision.
Is there any data or research that suggests academies are excluding more than LA schools? Many schools strongly avoid exclusions, as a high level will prompt a visit from Ofsted. Sometimes, if a failing school has become an academy, the new leadership have to take fairly drastic action early on, otherwise the school will not improve and all children will suffer.
In my opinion, there are too many children with complex issues coming up from primary school, whose behaviour hasn't been challenged or investigated, who cannot cope in a mainstream secondary where the environment and routine is totally different. I'm talking more about serious behaviour issues, SEMH and children with attachment disorder specifically. Unfortunately, it is not always easy to get an EHCP/statement which is what these children often need. I've seen countless children make it just months into year 7, racking up a long list of fixed term exclusions before being permanently excluded. They they usually end up in alternative/specialist provision where they thrive. I do wonder whether if strongly action was taken when these children were in primary, whether the outcome for that individual would be better.