I read Apple's responses as "We want to protect the reputation of a brand of device which is marketed as user friendly, secure and private". If they open up the

I read Apple's responses as "We want to protect the reputation of a brand of device which is marketed as user friendly, secure and private". If they open up the device to allowing anyone to deploy buggy software on, there will be a greater incidence of headlines similar to "iPhones with XYZ browser can be hacked!!", impacting the overall brand reputation for Apple products.