Microsoft has deep pockets so why not throw lawsuits at the wall and see if they stick, but from a technical perspective Microsoft didn't do anything wrong here

Microsoft has deep pockets so why not throw lawsuits at the wall and see if they stick, but from a technical perspective Microsoft didn't do anything wrong here. Now, do Microsoft need to redesign Windows to allow a larger percentage of security software to run in usermode? Yes. In the same way they redesigned it to run graphics and sound drivers in username because of the poor quality of third party vendors.